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Israel, Hizbollah and Iran: Preventing Another War in Syria

What’s new? A new phase in Syria’s war augurs escalation with Israel. As the Assad regime gains the upper hand, Hizbollah probes the south west and Iran seeks to augment its partners’ military capacities, Israel has grown fearful that Syria is becoming an Iranian base. Why does it matter? “Rules of the game” that contained Israeli-Hizbollah clashes for over a decade have eroded. New rules can be established in Syria by mutual agreement or by a deadly cycle of attack and response in which everyone will lose. A broader war could be one miscalculation away. What should be done? Russia should broker understandings that bolster the de-escalation agreement distancing Iran-backed forces from Syria’s armistice line with Israel; halt Iran’s construction of precision missile facilities and its military infrastructure in Syria; and convince Israel to acquiesce in foreign forces remaining in the rest of Syria pending a deal on the country’s future.

Executive Summary

The Syrian war has entered a new stage with the regime of Bashar al-Assad gaining the upper hand. Israel, no longer content to remain a bystander as Damascus’s position improves, is now jockeying to reverse the deterioration of its strategic posture. In this endeavour it has formidable obstacles to overcome: the regime is more dependent than ever on Iran, which Israel regards as its most implacable state foe; other enemies, particularly Hizbollah and Iran-backed Shiite militias, are entrenched in Syria with Russia’s blessing; and the U.S., notwithstanding the Trump administration’s strident rhetoric, has done little to reverse Iran’s gains. Yet Israel’s hand is not so weak. Russia has given it room to act against Iran-linked military interests and appears to be more interested in balancing contending fighting coalitions than returning every last piece of territory to the Assad regime’s control. But if Russia wishes to eventually withdraw or draw down its forces, it will need to broker rules of the game. Russia has indicated scant interest in doing so, but if it does not, hostilities between Israel and Iran may threaten its accomplishments, particularly regime stability. Israel’s initial concern was Syria’s south west, where it is determined to prevent Hizbollah or Shiite militias from approaching the 1974 armistice line and setting up offensive infrastructure in its vicinity. Their doing so, as Israel sees it, could mean a new front against it and put Hizbollah in a position to launch attacks from an area in which its Lebanese civilian constituencies would not have to suffer Israeli counter-attacks. The Israeli army, its planners fear, would be left to exact costs in Lebanon, Damascus or Tehran, with the risk of provoking a regional war.

For the moment, a “de-escalation zone” sponsored by Jordan, Russia and the U.S. is keeping Hizbollah and other militias at a distance from the armistice line. But there are signs this arrangement might not hold. Regime forces in January 2018 seized territory from a jihadist group in the zone, enabling allied militias to creep closer to the Israeli-occupied Golan. Isolated Hizbollah forces already are present in the zone and probing its edges. This deterioration could be slowed by bolstering the de-escalation agreement, an element of the 1974 separation of forces agreement between Israel and Syria. But the moment of truth will arrive when the war winds down in other theatres: will the regime make good on its vow to retake the whole country, including the south west? Israeli Prime Minister Benjamin Netanyahu seems to assume that if the regime pursues this goal in earnest, inevitably the assistance of foreign forces will follow. More broadly, Israel wants to prevent its rivals from consolidating a permanent military presence anywhere in Syria, which, it fears, would strengthen their hand in future wars as well as their influence today in Lebanon, Jordan and the Palestinian arena. Iran is of particular concern: Israel’s red lines seek to block it from establishing an airport, naval port, military base, permanent presence of militias or precision weapon production facilities for Hizbollah. Israel has already demonstrated its resolve to disrupt the construction of this sort of major military infrastructure. Russia by and large seems content to let this pattern continue and neither Iran nor Syria can stop it.

Yet Israel’s strikes against militiamen will prove riskier to pursue and easier to thwart, for instance by integrating the fighters into the Syrian army or simply having them don its uniforms. Israeli officials are also concerned at the prospect of a territorial corridor controlled by Iran-linked forces stretching via Iraq into Syria and Lebanon, which arguably could facilitate the movement of fighters and materiel. This development, too, will be harder for Israel to stop, particularly in Syria’s east, since its intelligence and military capacities decrease with distance from the Golan. Only Moscow is in a position to mediate a bolstering of the de-escalation agreement. Unless it does, the rules of the Syrian game are likely to be worked out through attack and response, with risk of escalation. Attacks by Iran-backed groups over the armistice line dropped over the last couple of years, but Assad’s January 2018 seizure of adjacent territory may augur an increase. Israel too may attack, in the form of limited strikes to prevent Hizbollah from acquiring precision weapons facilities in Lebanon, which it has accused Iran of pursuing. Israel’s military establishment assesses it could do so without provoking an all-out confrontation. Perhaps, but Hizbollah has signalled that the consequences of such a strike are unpredictable. A broader war could be only a miscalculation away. Regional changes make that miscalculation more likely. An increasingly assertive U.S.-Saudi strategy, with help from Israel, is taking shape to pressure Iran militarily, economically and diplomatically. These powers have adopted an activist posture to establish the deterrence vis-à-vis Iran that they feel was lost during the Barack Obama administration. Hizbollah and Iran of course have ways to reply. Neither Hizbollah nor Israel is a pawn of its allies and both have reasons, particularly the threat to civilian populations, to avoid a major escalation. But hostilities are unlikely to remain local.

In Syria’s south west, Russia appears to be the sole actor capable of mediating understandings to prevent an Iran-Israel escalation across the country. The best currently anticipated outcome would be a deal whereby Iran and its partners forego building major military infrastructure, including but not only in Syria’s south west, but retain significant influence in the country through other means. It is difficult to imagine a reversion to the pre-2011 situation, when the Syrian state, while allied with Iran, was not an arena for an open Iranian presence and military operations. For the foreseeable future, Iran will continue to be a pillar of the regime’s security. But it risks undermining its investment should it overplay its hand. Everyone stands to lose from an intensification of the Syrian war, first and foremost the Syrian people. So too do Israel and Lebanon, since an altercation between them involving Hizbollah could ignite another war across their borders and beyond. As for Damascus and its backers, a massive campaign by Israel will do enormous damage to their achievements, perhaps even destabilising the regime itself, which would sow discord between Russia and Israel. Gradually stabilising Syria would be a wiser course, and the only viable one toward an eventual settlement.


Israel long has had a complex relationship with Syria. Under President Hafez al-Assad, the Syrian regime was a Soviet client that fought wars with Israel in 1967 and 1973, and clashed with its neighbour on numerous other occasions over the Golan Heights, the territory that divides the two countries and which Israel occupied in 1967 before relinquishing a portion after the next war. In the 1980s, as a result of the Iran-Iraq War and Israel’s 1982 invasion of Lebanon, Syria grew closer to Iran, an even more suspect partner than the Soviets from Israel’s perspective. Damascus, which had been a strategic ally of Tehran since the 1979 Islamic revolution, facilitated the development and arming of Hizbollah, the Lebanese Shiite militia that has killed more Israelis since its 1982 establishment than any of Israel’s other foes. Yet, ever since the 1974 Separation of Forces Agreement formalised the end of the previous year’s October War, Syria has secured the resulting armistice line. The agreement created a UN buffer zone that ran from Mount Hermon/Jabal al-Sheikh in the north to the Yarmouk River in the south and included the town of Quneitra. Monitored by the UN Disengagement Observer Force (UNDOF), an observer mission created for the purpose, the buffer lies on the Golan Heights between the Israeli-occupied part and the rest of Syria. For decades this de facto border was Israel’s quietest – including the boundaries with Jordan and Egypt, with which Israel has peace agreements.

The outbreak of the Syrian civil war in 2011 posed an unprecedented dilemma for Israeli policymakers and security officials. Repelled by all parties to the conflict, Israel chose not to choose between the Iran-backed regime (which its officials derided as “plague”) and the fragmented and, as the war escalated, increasingly radicalised opposition (scorned as “cholera”). Israel instead kept its distance from the vortex, waiting to see who would emerge victorious. In the interim it focused on how to maintain security and stability, especially in the north of the country, with violence raging across the armistice line. This report analyses how Israel has dealt with the conundrum presented by the war in the context of the region’s changing geopolitics. It is based on field research mainly in Israel, but also in Syria, Lebanon, Russia and Iran. After explaining the evolution of Israeli policy, the report offers policy ideas for disentangling, as much as possible, the Israel-Syria from the Israel-Hizbollah conflict, for the benefit of Israelis, Syrians and Lebanese alike.

II.Israeli Policy toward Syria

A.Israel’s Red Lines

As the war in Syria unfolded in 2011 and 2012, Israel found itself confronting two dangers: that the Assad regime would win and that it would lose. A win, especially with Iran’s backing, would fix the regime even more firmly in Tehran’s orbit. A loss would deal a painful blow to what Iran refers to as the “axis of resistance” – but Israel’s victory might be pyrrhic, if radical Islamist groups, including jihadists, seized control of Syria. This threat seemed especially big at a time when the Muslim Brotherhood was ruling Egypt and the “Arab spring” was still known as such, a challenge to the rulers of other states such as Jordan, Israel’s neighbour and partner. With no single good strategic option, the Israeli military’s northern command shaped the country’s initial response, seeking to prevent, to the extent possible, the erosion of its position. Israel announced a series of red lines designed to secure its home front and bolster adjacent states’ stability. Though its red lines sometimes overlapped with another stakeholder’s interests, Israel considered its posture neutral; outside actors, however, saw Israel as taking sides. At first there were three red lines, with a fourth added shortly thereafter. The first two pertained to Hizbollah. Israel made clear it would prevent the Shiite militia from bringing into Lebanon “game-changing” weaponry, the definition of which has shifted over time, and from building or seizing control of offensive infrastructure across the armistice line in Syria’s south west, including Syrian army bunkers and bases presently under opposition control. This red line extends to Islamic Revolutionary Guard Corps (IRGC) advisers, other Iran-backed Shiite militias or anyone else.

After the 2006 Israel-Lebanon war, Israel and Hizbollah readied themselves for the next round, reaching a relatively stable equilibrium based on mutual deterrence. Hizbollah brought Iranian arms into Lebanon through Syria; Israel interdicted the transfers only intermittently for fear of provoking an escalation. Israel tended to hesitate before striking even when the weapons were deemed significant (long-range and high-precision missiles) and the conditions ideal. When Hizbollah entered the war in Syria, however, Israel began to strike more aggressively to prevent the Shiite militia from using the fog of war to screen the acquisition of “game-changing” weaponry. Second, Israel also declared its intention to block the establishment of offensive infrastructure east of the occupied Golan, whether by Hizbollah fighters and Iranian proxies or by forces linked to al-Qaeda or the Islamic State (ISIS). Israel feared that Iran and its partner forces would entrench themselves adjacent to the armistice line, enabling the opening of a new front – one where Lebanese civilians (especially Hizbollah’s constituents) would be out of the line of fire; Israel would have insufficient justification, its officials fear, to readily reply in Lebanon.An Israeli official described the strikes in January 2015 (killing a prominent Hizbollah figure, Jihad Mughniyeh, along with several other members of the organisation and an Iranian officer) and December 2015 (killing Samir Quntar, who had been released in a 2008 prisoner exchange with Hizbollah and subsequently became a senior figure in the organisation) as the most salient instances of enforcing this red line. These strikes are just two of more than twenty Israeli responses to alleged attacks in the three years after Hizbollah’s deployment to Syria. From the onset of the fighting until Russia’s September 2015 military intervention, Israeli officials sought a buffer zone – free of any hostile forces, including Assad’s army, which they saw as an extension of Tehran’s – of about 20km; after Russia deployed, and when Iran and its allies later gained the upper hand in the war, Israeli officials began to demand a 60-km buffer, though they grudgingly came to terms with a Syrian military presence within that area. (See map in Appendix A.)

Israel’s third red line was enemy fire into territory it controlled: Israel threatened to reply in every instance, regardless of the perpetrator or intent. Until September 2016, Israel’s policy was to retaliate against the regime in reaction to any and all stray fire based on the fact that it was the sovereign power. But when rebels, under pressure, began to fire into Israel to provoke a response against the regime, Israel started firing back at them as well. The fourth red line was never announced as such. In mid-2015, when a coalition of Syrian rebels moved toward Sweida and Jabal Druze on the south west border with Jordan, and Jabhat al-Nusra, then the Syrian al-Qaeda affiliate, moved northward from Quneitra, Israel cautioned Syrian rebels against attacking the Druze population of the area, particularly in the village of Hader, near the armistice line. The prime minister announced he had instructed the military “to take all the necessary actions” to protect the village’s residents. This de facto red line never attained the same prominence as the others because the risk of carnage in the village quickly faded, re-emerging only in November 2017. Israel’s leadership felt forced to commit to this course of action because it faces strong pressures from its own Druze population, who serve in the Israeli army and therefore are linked with Israel’s Jewish population in what they call a “blood pact”, which many Israeli Druze claim extends to defending their relatives in Syria.

Israel also used soft power to protect its boundary. Since 2013 it has provided aid – food, clothes, blankets, baby formula and medical assistance – to the residents of a narrow band of territory within Syria east of the Israeli-occupied Golan. Control of Syrian land abutting the armistice line is split between three groups and alliances: Jaysh Khalid bin al-Walid (formerly Katibat Shuhada al-Yarmouk, the Yarmouk Martyrs’ Brigade), an ISIS affiliate, in the southern part of Quneitra governorate; Jabhat al-Nusra (now part of Hei’at Tahrir al-Sham and formerly al-Qaeda’s Syrian affiliate) and other opposition forces, along the central stretch of the armistice line (including the town of Quneitra); and the regime, Hizbollah and Druze allies in the governorate’s north, predominantly in Hader. Israel has focused aid provision in the vicinity of Quneitra to minimise the benefit to Jaysh Khalid and Hizbollah-friendly Druze. Some native residents remain in this central area, in addition to hundreds of thousands of internally displaced persons (IDP), especially from Daraa and Damascus, who arrived in particularly large numbers in 2014 (and more recently in late June 2017) when fighting escalated in Daraa. Thousands of the IDPs moved to tent camps adjacent to the Israeli-Syrian ceasefire line, mostly within the buffer zone, thinking the UN and proximity to Israel would offer a modicum of protection. Israel has sent some humanitarian aid to the camps, including through the operation of a field hospital on its side of the armistice line. Some aid (eg, flour for bakeries and school supplies) goes to support communities in which combatants live in order to dissuade them from firing on Israel for fear of losing the assistance, as well as to improve public opinion vis-à-vis Israel. Israeli officials vehemently deny Israel is providing military aid to jihadist groups like ISIS and al-Qaeda.

B.Enter Hizbollah

Israel adopted a more assertive stance in late 2012 when Hizbollah deployed in Syria, and particularly in May 2013 after the Shiite group won a key battle at al-Qusayr, a village near the Lebanese border that is strategically located near the highway connecting Damascus to Homs and the Syrian coastline. Hizbollah’s entry into the war extended Israel’s decades-old battle with the group to Syrian territory and entailed the interlocking of three hitherto separate conflicts: between Israel and Syria, between Israel and Hizbollah, and among the various parties to the Syrian civil war.

In Syria, fighting for the regime’s existence, Hizbollah has easier access to arms, including missiles of greater range, power and precision. As a result, it has improved its arsenal to the point that Israel’s concept of what constitutes “game-changing” weaponry – the sort that Israel has attempted to block – has changed. Israel largely has given up on interdicting long-range missiles, of which Hizbollah now has many, and shifted to preventing the group’s acquisition of precision weaponry that would enable it to target Israel’s most sensitive locations, such as downtown Tel Aviv, Ben Gurion airport, and gas extraction and production facilities. Israeli officials are convinced that the next war with Hizbollah will exact a heavy toll on the home front, and as such Israel has defended its new red line with vigour. Since a foray on 30 January 2013, the first time in over five years that the Israeli air force carried out an attack inside Syria, Israel claims to have launched nearly 100 aerial strikes. (See chart of Israeli airstrikes in Appendix B.) Hizbollah’s deployment in Syria also created the possibility that at some point its forces would move south. When these forces did just that in coordination with the regime in February-March 2015, six months before Russia’s military intervention, Israeli officialdom decided to prevent Hizbollah and other pro-Iranian militias from seizing territory in the vicinity of the Israel-Syria armistice line, lest they dig bunkers or erect missile batteries there. Israel’s professed plan, in the event the regime’s campaign seemed likely to succeed, was to create either a no-fly zone or an IDF-controlled buffer zone 20km inside Syria. An Israeli official explained that failure to do so would badly erode his country’s strategic position and lead it into a war he said it did not want:

Hizbollah will win an exchange of blows. They will fire at our civilians, scoring points for “resisting Israel” while we will be limited to pummelling fighters who can easily be replaced. It is unclear how long we’d be able to absorb this before we’d have to respond on a bigger scale. And if they strike the proverbial kindergarten, all bets are off. Before we know it, we will be looking at exacting costs directly from Beirut, Damascus or Tehran – a conflagration we’d rather avoid.

But when the rebels counter-attacked and pushed northward in April-June 2015, the plans Israel had been considering became unnecessary.

III.The Russians Are Coming!

A.Russia to Assad’s Rescue

Syrian rebels captured nearly all of Idlib governorate in the first half of 2015 and threatened to advance on Lattakia as well as southward through the Ghab plain to link up with rebel-held areas in the Hama and Homs countryside. Judging the situation critical, the Syrian regime and its Iranian ally sought and received military support from Moscow in July. To facilitate its deployment, Russia constructed an air base at Hmeimim, south-east of Lattakia on the Mediterranean. Russian forces included T-90 tanks, artillery, warships, military advisers and special forces. The next month, Russia started moving forces toward Lattakia and set up a joint operations room with Iran, Iraq and Syria, soon to be joined by Hizbollah, with the ostensible aim of fighting ISIS. On 30 September, the upper house of the Duma, Russia’s parliament, authorised military operations in Syria; the first airstrikes occurred within hours of the vote. Prime Minister Benjamin Netanyahu flew to Moscow on 21 September, days before the Russian intervention, to establish Israeli-Russian coordination and, subsequently, a de-confliction mechanism to prevent accidents. This mechanism comprises a hotline between IDF headquarters in Tel Aviv and Russia’s Hmeimim air base, direct communication between the Russian and Israeli deputy chiefs of staff, and regular consultations at multiple levels of the respective defence establishments. The hotline demonstrated its value almost immediately, in late November 2015, when Israel refrained from firing on a Russian airplane flying above the Golan. For its part, Moscow has yet to activate its defence systems in response to Israeli strikes.

Russia’s intervention soon shifted the war in Assad’s favour, stopping the momentum of the rebels and then, in Aleppo in late 2016, decisively turning the tide. It became increasingly clear that the regime would not be defeated – and that, to the contrary, it likely would continue its attempt to regain control over the whole country. The success of Russia’s intervention put paid to Israeli officials’ hopes (already faint, during the Obama administration’s tenure) that the U.S. would back the rebels more strongly and counterbalance Russian support for the regime. Beyond changing the course of the war, the Russian intervention introduced four strategic dilemmas for Israel and constrained its options for dealing with them:

  • It enabled Hizbollah and Iran, Israel’s most potent enemies, to expand their areas of operations and advance toward or even up to the armistice line. As Israel sees it, were Moscow to back Assad’s recapture of the south, the result would be the same: Hizbollah and Iranian forces would reach the Golan Heights and ultimately build offensive infrastructure there.

  • It constrains Israel’s freedom of military manoeuvre. After Turkey, in November 2015, shot down a Russian military aircraft that it accused of violating its airspace, Russia deployed S-300 and S-400 air defence systems in Syria. Israel can counter the former; the latter, operated only by Russian personnel, pose a much greater challenge. “A fly can’t buzz above Syria without Russian consent nowadays”, observed an Israeli defence official. Moscow has built up its capacities more broadly in the country, suggesting plans for an extended presence that would make it part of the regional military landscape for the foreseeable future, notwithstanding its occasional professions of imminent withdrawal.

  • It raised the possibility that the regime’s campaign to recapture the east, also backed by Russia, would open a land bridge from Iran to the Mediterranean. Though not all military analysts agree, Israel sees the strategic stakes as enormous: such a corridor could facilitate the transfer of both weapons and Iran-backed Shiite militias across state borders and enable Iran to establish a presence across a wide area with potential to threaten Israel. Seen from Israel, such a corridor would provide Tehran an affordable alternative to costly shipment by air. Were the corridor also to thicken Syrian-Iraqi-Iranian economic cooperation, the density of commercial traffic could make it harder for Israel to detect and intercept arms convoys. Russia does not seem particularly concerned by this prospect and has offered Israel no help in forestalling it.

With chances growing that the regime and its allies would retake the south, Israel sought to bolster anti-regime militias as well as extend its sway over the population beyond the armistice line. As a prominent Israeli analyst said, Israel wished “to ensure public support among residents of south Syria for rebel non-aggression toward Israel and to increasingly legitimise the role of Syria’s rebels as Israel’s border guards”. In May 2016, Israel formally upgraded its efforts and the army established a Syria Liaison Unit to improve delivery of humanitarian aid under its Good Neighbour policy. In 2017, the army built a new clinic, east of the fence yet west of the UN buffer zone, making it possible for thousands to receive regular medical treatment each week without crossing the Israeli barrier on the western edge of the demilitarised zone. These investments notwithstanding, soft power could not compensate for the weakening of Israel’s strategic position. Israel’s greatest foes are better armed and trained than before, and in theory could enjoy the protection of Russian warplanes. Iran is operating in closer proximity to Israel. An Israeli foreign ministry official worried, “Syria is on its way to becoming a Russian-Iranian protectorate”.

B.Israel’s Updated Red Lines

These developments have forced Israel to update its red line policy. It has continued to block the transfer of advanced weapons to Hizbollah, so far with Russia’s tacit consent. Israeli officials believe that in the main they have frustrated Hizbollah’s efforts to smuggle precision weapons into Lebanon, which may explain why the movement tried to establish an arms production capacity in its home country. According to Israeli officials, Hizbollah for a time froze those efforts in light of Israeli threats,though they argue that since late 2017, Iran-backed efforts to build such workshops shifted to Syria, where Israel is reported to have struck two, and since then, in January 2018, back to Lebanon again. Israel also is unwilling to countenance the basing of Hizbollah’s advanced, long-range rockets in underground Syrian military facilities in the Qalamoun mountains, some 50km north of Damascus. Rockets in those mountains, Israel worries, would allow Hizbollah to threaten much of Israel with less concern for direct Israeli retaliation that would cause mass casualties among Lebanese civilians and damage civilian infrastructure. That war-fighting strategy might be more difficult for Israel to justify internationally if the initial strike came from a neighbouring country,and would risk drawing in the Syrian army. Israel has expressed disappointment at Russia’s stance toward Iran’s presence in Syria. After the regime’s victory in east Aleppo made clear that Assad would stay in power, the Astana negotiations in May 2017 produced an Iranian-Russian-Turkish memorandum on de-escalation zones, including in the south west. From Netanyahu’s perspective the agreement had severe shortcomings, particularly that it legitimised Iran’s and Turkey’s military involvement in Syria (by formally making them guarantors and monitors of de-escalation and, potentially, giving them a role in defeating jihadist groups) and stayed silent about Hizbollah and Iran-linked forces, effectively enabling them to maintain some presence in the south west.

Israel therefore updated its red lines – signalling it would take matters into its own hands if necessary to keep Iran from establishing a permanent military presence in Syria. These red lines concerning Iran, which have not changed but have become more detailed over time, include:

  • No Iranian seaport – Israeli shorthand for no Iranian base for maritime activities in the Mediterranean, which would enable Iranian submarines to threaten the Israeli coast as well as gas rigs, which Israel considers of strategic importance. Israel, in addition to depending on gas for domestic electricity generation, is becoming a significant exporter, including to Jordan, which has helped line up Amman behind this Israeli demand.

  • No permanent Iranian military bases and no permanent presence of Shiite militias trained and commanded by Iran. Looking beyond the present phase of the fighting, Israel does not want Syria to become an Iranian military staging ground, a node of Iran’s “forward defence” strategy. Thousands of non-Syrian Shiite militiamen stationed permanently in Syria under IRGC command could emerge as a potent fighting force akin to Hizbollah. While Israeli officials acknowledge that insisting on their evacuation sets a high bar, fighters remaining under Iranian control and protection could complicate Israel’s operations in the event of combat. Israel is reported to have carried out at least two airstrikes in Syria upon a purported Iranian military base under construction to demonstrate its resolve. Asked about them, an Israeli defence official said: “So far, so good on the setting of new red lines, with the emphasis on ‘so far’”.

  • No Iranian airport, to ensure the monitoring of aerial supplies of weapons, militias and troops to Syria. Iran already lands commercial airplanes in the Mezzeh air base near Damascus but Israel’s intelligence regarding the facility has enabled it to repeatedly strike missile shipments there. Israel wants to avoid the establishment of an Iranian airport, or in fact any airport at which Iran has free rein, particularly in more distant areas of Syria, where it would be harder to gather intelligence and longer bombing runs would be required.

  • No high-precision missile factories. This stricture applies to both Lebanon and Syria. Israel believes that after Hizbollah froze its attempt to establish such capability in Lebanon, Iran has continued to pursue this capacity in Syria.

Moscow believes these red lines extend beyond Israel’s legitimate security needs, and reportedly has rebuffed requests that it confront Iran on these issues. Moscow tends to see Hizbollah in a positive light, generally views Iranian political and economic interests in Syria as legitimate, and respects Syria’s sovereign decision-making, at least on certain issues. A Russian diplomat said:

Israeli officials repeatedly tell us that Iran is fighting in Syria primarily because of its ultimate agenda of destroying Israel, that Iran is motivated by theology rather than state interest, and that we should create an Iran-free Syria. We want to take Israel’s interests into account, but it is impossible to take such arguments seriously.

Even were Moscow more inclined toward Israel’s positions, it may lack the capacity and leverage to compel Iranian compliance with all of Israel’s demands. Even in cases where their interests diverge, securing even small concessions from Damascus and Tehran appears tough for Moscow. It is unlikely to put its credibility on the line in an uncertain attempt to achieve all of them. In particular, Russia might see benefit in the presence of at least some Iran-backed militias; their precipitous withdrawal, given the weakened state of Syria’s forces, could leave the regime exposed, thus ultimately adding to Russia’s own burdens. Syria’s south west presents a unique challenge, given the proximity of the territory to the Israeli-occupied Golan. In July 2017, the U.S., Russia and Jordan negotiated a ceasefire in south west Syria between the Syrian army and mainstream opposition forces providing for the three states to jointly operate a monitoring centre in Amman. In November 2017, Russia, the U.S. and Jordan, after lengthy negotiations, agreed to precisely delineate the territories in question, defining an opposition-controlled de-escalation zone surrounded by a 5km-wide strip, controlled by the Syrian army and with access monitored by Russian military police, into which entry by “foreign forces or foreign fighters” was forbidden. The tripartite agreement permitted continued fighting in the areas it delineated as ISIS-controlled. (See map in Appendix A.)

ear what will happen in the Yarmouk valley and Beit Jinn enclaves. The November 2017 agreement delineated the two as controlled by jihadist rebels (respectively, by the ISIS-affiliate Jaysh Khalid Bin al-Walid and by Hei’at Tahrir al-Sham, alongside local insurgents), and therefore excluded from the ceasefire, subject to recapture by either Damascus or the opposition. In early January 2018, after months of intense fighting, the opposition in the Beit Jinn enclave surrendered to the regime, which now controls a triangular patch at the intersection of the Syrian, Lebanese and Israeli boundaries. This development means that foreign (including Iran-backed) fighters, per the terms of the July agreement, can now be stationed 5km from Israel’s fence. Israeli officials fear Hizbollah will capitalise on this shift to establish offensive infrastructure in the Golan Heights. Further to the south, according to some accounts, the U.S. and Jordan agreed to push rebels to attack the jihadists in the Yarmouk valley in return for Russia’s agreement to exclude Hizbollah from the area; it is unclear that the U.S. can do so if it is also terminating its support to the rebels. As with Israel’s other red lines, the operative question is less what Israel thinks of the deal and more whether Russia has the will and capacity to implement it. Given its ambiguities and the winding down of hostilities elsewhere in the country, freeing the regime and its allies to refocus their attention sooner or later on the south west, Israel and at least some Russian officials view the agreement as likely to erode before an intra-Syrian agreement over the country’s future is reached. Unless the de-escalation zone is bolstered, they are probably correct.

IV.U.S. Rollback or Russian Balancing?

Israel’s political echelons are pleased with what they hear about Iran from the administration of President Donald Trump. The administration’s harsh rhetoric suggests the U.S. plans to roll back what it sees as Iran’s aggressive regional expansion. Israel, which long has been clamouring for a harder line from Washington toward both Tehran and its friends in the Middle East, applauds the tough talk. It cheers the U.S. bombing of an airfield in Syria after the Assad regime’s chemical attack in Khan Sheikhoun in April 2017; the U.S. strike on regime forces near al-Tanf on 18 May 2017; the refusal to certify the Iran nuclear deal because of alleged disproportionate sanctions relief in return for Tehran’s nuclear concessions; the designation of the IRGC as a terrorist entity; new sanctions against Hizbollah; denunciations of the Huthi rebels in Yemen; and determination, in coordination with Saudi Arabia, to restore deterrence vis-à-vis Iran. Since Trump’s May 2017 visit to Riyadh, the prospect of a U.S.-backed Israeli alliance with Arab states against Iran has come to seem more realistic. Israel, however, quickly tempered its great expectations of the White House when it came to Syria. When Trump proclaimed, in his Iran policy announcement, that his administration “will work with our allies to counter the [Iranian] regime’s destabilizing activity and support for terrorist proxies in the region”, Israel hoped Syria would be among the first places where Trump would act forcefully. It was not. During the administration’s first year, it waited-and-saw whether Moscow’s sense of its own self-interest might lead it to restrain Iran in Syria. Washington showed little inclination to directly challenge Iran-aligned forces west of the Euphrates, much to Israel’s disappointment. Instead of prioritising the fight against Tehran and its allies and issuing a credible threat of force in Syria; providing rebels (notably southern ones from al-Tanf) with the resources to block the purported Iranian land bridge in the south; and strongly backing Iraqi Kurds in the wake of their independence referendum to enable them to foil a northern land bridge and otherwise keep Iran occupied, Trump, in the words of an Israeli intelligence official, opted to “pacify Russia”.

Today there are some indications that this approach could change, with the administration articulating determination to combat Iran’s influence in Syria and terminate Assad’s rule. Still, Israel remains in a bind because Moscow, which seems set to stay in Syria for some time, has been a faithful if sometimes tentative partner for the regime, Hizbollah and Tehran. It has sought to balance their concerns with Israel’s and find a modus vivendi between the two sides. True, Russia has turned a blind eye to virtually all of the nearly 100 Israeli strikes over the past five years. A Russian diplomat offered a resigned assessment: “These strikes don’t contribute to stability. We say that to Israel. But nobody is an easy partner”. But benign disregard is not enough for Israel, which has little hope it can push Russia to go much further vis-à-vis Iran. Would Israel try to contain Hizbollah on its own, including by launching a pre-emptive attack to prevent the Shiite group from establishing the capacity to produce precision weapons? Israeli defence officials say the early December 2017 strike in Syria on such a workshop demonstrates their military could carry out a more comprehensive strike on comparable sites, with Russia’s tacit acquiescence and without provoking an all-out war. Even if faced with an attack on facilities in Lebanon, they believe, Hizbollah would be deterred from replying and escalating beyond a limited threshold, since the group realises that in a wider conflict its forces would be decimated. More likely, according to Israeli officialdom, is an abbreviated exchange, falling well short of war, that would leave Hizbollah without the capacity to produce precision weapons.

Israel’s calculation relies on the correct calibration of its targets, its enemies’ being deterred, and on accurately reading Hizbollah and its backers. That could turn out to be risky: the movement has been signalling for months that since the Syrian conflict has become so complex, any fighting might escalate rapidly, denying Israel a limited war. Further complicating these calculations are rapid regional and global developments, which have upended the conventional rules of the game that have more or less kept the peace since 2006. Particularly significant here is differentiation between strikes in Syria and Lebanon, on one hand, and Israel’s policy of ambiguity (that is, not taking responsibility) regarding such strikes, on the other. Both principles loosened up in 2015 and 2016 as Hizbollah’s involvement in Syria deepened and Russia’s deployment gave a decisive advantage to the regime. Until January 2015, all parties largely adopted a principle of “what happens in Syria, stays in Syria”. Israel confined its aerial strikes on Hizbollah weapons convoys to Syrian territory, cognisant that the same sort of attack on Lebanese territory could lead to full war. The “keep it in Syria” rule also injected urgency into Israel’s efforts to prevent Hizbollah from entrenching itself on the Golan, since abiding by it would enable the group to fight a war of attrition against Israel from Syria with less risk of catastrophic damage to Lebanon. Similarly, regarding Syria, Israel did not take credit for strikes against Hizbollah convoys in Syria to avoid embarrassing the Assad regime and provoke a reply. The Assad regime, for its part, long refrained from firing at Israeli aircraft carrying out strikes in Syria against such convoys.

Hizbollah largely has continued to live by this rule, enduring occasional strikes without reply as the cost of being able to operate in Syria. Movement leader Hassan Nasrallah’s declaration that Lebanon and Syria henceforth would constitute a single theatre has materialised on only two occasions. A leading figure in the movement explained: “We are not acting alone. We have to keep in mind and respect what the Syrian government wants”.By contrast Hizbollah considers Lebanon its home turf: any Israeli attack there, whether pre-emptive or reactive, would all but certainly occasion some form of reply. Iran seems to have adopted the same approach: after Israel struck two targets near Damascus, widely reported as Iranian, in November and December 2017, Tehran denied the strikes had occurred and, at least so far, has not responded militarily. Since March 2017, as the tide turned sharply in the direction of the regime and its allies, the erosion of the “keep it in Syria” principle quickened. Israel could not hide the first open violation of its policy of ambiguity, when its Arrow missile defence system shot down a Syrian anti-aircraft missile fired against Israeli planes attacking in Syria. Later, on several occasions, its leadership took responsibility for strikes against Hizbollah, Syrian and even Iranian sites, whether to reinforce its deterrence message or, as Netanyahu’s detractors allege, out of electoral considerations.Today Israel echoes Hizbollah’s rhetoric: in the next war, Israel will treat Lebanon and Syria as a single front. In an indication that the Syrian regime is moving in the same direction, it fired on Israeli aircraft several times this year, and in a particularly telling case, launched anti-aircraft missiles at an Israeli aircraft gathering intelligence over Lebanon in what, in Israel at least, was widely regarded as an attempt to limit Israeli freedom of action.

V.Preventing the Next War

With the Assad regime having gained the upper hand, the jockeying for the next stage has begun. Israeli strikes against Iranian sites in early December 2017 appear to have been opening tactical salvos. Israel reportedly launched a diplomatic salvo as well. First, Israel purportedly passed a message via a third party to Bashar al-Assad threatening him personally as well as with military intervention in the war if he aids Iran in its regional agenda. In the second message, allegedly conveyed to President Putin in late November or early December, Netanyahu is said to have claimed that to maintain Israeli red lines with respect to Iran’s military presence, Israel would be prepared to incur a cost in terms of its relations with Moscow. Neither of these threats sound particularly credible, especially if understood in maximalist terms. Israel would be taking a serious risk if it were to militarily threaten the Assad regime’s stability, say by aerially striking Assad’s palace, and it can ill afford a direct confrontation with a global superpower on its very doorstep. It is also far from certain that even if Netanyahu is willing to take risks, Israel could engineer a reality in Syria better aligned with Israel’s interests. To prevent Syria from becoming a theatre for Hizbollah-Israel and Iran-Israel wars, there are two key realms to contend with.

A.Across the Armistice Line: South-west Syria

The south west is now largely quiet because of the ceasefire and the focus on other parts of the country. With the Astana deal and the subsequent U.S.-Russian-Jordanian agreement, most regime and allied forces are focused elsewhere, primarily the east, north west and Damascus outskirts. Optimally this situation would endure until there is a diplomatic settlement to the entire Syrian war. Yet a diplomatic solution is still a long way off and there are reasons to suppose the de-escalation agreement might not endure that long. The Assad regime repeatedly has stated its intention to retake all of Syria. Since it is unlikely that the Syrian army would be able to take the territory by itself, it would require Hizbollah and/or militia assistance.

Should this coordinated campaign come to pass, Israel has indicated it will strike to prevent hostile forces from approaching the armistice line, aerially if it can and if not with artillery. Should fighting start, regardless of who fires the first shot, it is unlikely to end quickly. Israeli planners have limited options for putting a decisive end to tit-for-tat hostilities, especially of the sort meant to cause attrition. Hizbollah would have many good targets, while Israel would have few unless it expanded the exchange into Lebanon, which would risk a major war on what many Israeli officials fear could be considered weak grounds. The costs to Hizbollah would be relatively low, since it does not have any natural constituency in this area, while Israeli strikes would antagonise the local population, which could benefit Hizbollah. A major war would be only a miscalculation away. Should pressure build in Israel for a more robust response, the government would choose among a series of bad options: target Hizbollah in Lebanon; strike Syrian targets in an effort to force Damascus or Moscow to rein in Hizbollah; or, should strain mount to levels it deems unbearable, launch an incursion into Syria to push Hizbollah back. All have the potential to trigger a wider war that drags in a variety of actors, including the Syrian government. The current lull offers a chance to preclude this scenario by reinforcing the November agreement. True, Israel already has a territorial buffer in the form of the occupied Golan Heights, the need for which has been one of Israel’s main arguments for retaining control over these lands; in essence, Israel today is demanding a new buffer denuded of foreign forces to protect its original buffer. This new buffer would extend 40km into Syrian territory roughly along the Deraa-Damascus road, even further than the exclusion zone to which the U.S., Russia and Jordan agreed (see map in Appendix A). With no practical way to eject the fighters already there, a zone of this depth is unlikely to materialise. The regime, for its part, considers any buffer on its territory unjustifiable. Yet the perpetuation of the de-escalation arrangement is the best way to stabilise Syria’s south west, which is why the regime adheres to it and should help to bolster it, its exclusion provisions notwithstanding.

To do so, Moscow at the very least should not provide air cover for a regime campaign that includes Hizbollah or militias to retake these areas, and it should use its control of Syria’s airspace to prevent the Syrian army from using in the south west its remaining air assets. That in and of itself is unlikely to dissuade the regime if it is determined to move into the area, especially should the capacities or discipline of local rebel forces diminish as a result of the termination of U.S. covert assistance. Russia, as the only power with leverage on all sides, will need to broker a strengthened deal. One formula to lessen the regime’s incentive to break the deal would be for rebels to hang on to their weapons for self-defence and policing and, in return, accept the state’s legitimacy (though not explicitly the regime’s) and the return of its administrative organs (staffed, to the extent possible, with local personnel). Rebels would maintain autonomy over their own security, which would require ensuring that they have sufficient weaponry and continuing to pay their salaries, perhaps with a Gulf country stepping in for the U.S. The regime and Russia could plausibly claim that the state had restored its sovereignty. Israel would have to settle for a smaller exclusion zone than it has demanded, but this formula would offer a realistic way to keep its foes away and thus reduce the odds of a regional conflagration. Stability in the area also could facilitate a fuller return of UNDOF, an element of the 1974 Israeli-Syrian separation of forces agreement, which both Israel and Syria claim to want to restore.

The formula to bolster the de-escalation resembles earlier “reconciliation” agreements, including in southern Syria, responding to efforts by Damascus and Moscow to reinforce the territorial integrity of the Syrian state, but would differ in two key respects. First, the rebels would remain in place, keep their weapons and retain sole responsibility for local security, backed by the implicit threat of Israeli force. Russian forces, possibly in cooperation with Jordan, could provide substantive monitoring. Second, the rebels have already implemented a ceasefire and most regime and allied forces are fighting far from the south-west front. This fact means that, as opposed to earlier agreements, bolstering the ceasefire would not provide a military advantage to the regime by allowing it to transfer forces elsewhere. Perhaps the most significant challenge to this arrangement would be Russia’s ability and willingness to deliver the regime and Iran should they demur and prefer to advance their military campaign. It is particularly unlikely that the two would accede to this arrangement for the southwest so long as Israel continues to strike their assets in other parts of the country – which is why any local ceasefire is unlikely to endure without a broader modus vivendi.

B.Israel’s Near Abroad: Brokering a Modus Vivendi in Syria

Barring the unexpected, Bashar al-Assad will remain at the helm for the foreseeable future and the country, or at least the considerable amount of it that the regime controls, will remain under the influence of Iran and its allies. The regime will continue to depend on Iran for security and control of its own territory. Tehran has already set down roots in the Syrian economy, with stakes in the oil, gas, mining, agricultural, power and communications sectors, among others. Iran’s ground presence and belief that maintaining a friendly Syria is an existential concern means it is all but inconceivable that the Iranian military could be pushed from the country as part of an eventual settlement of Syria’s war, as Israel demands. That said, it is not clear whether or how Iran plans to use this military presence. A leading Hizbollah figure suggested that Iran may in fact be seeking to protect its substantial investment in Syria by consolidating its position there, which may work as a disincentive for escalation and instead encourage a modus vivendi:

Iran’s long-term objective is a stable Syria friendly to Iranian interests. The partner for that is Bashar al-Assad. It would be completely against Iran’s interest to burn this asset.

An adviser to Iran’s supreme leader, Ali Khamenei, made a similar point about his country’s aims in Syria, alleging:

Neither Iran nor Hizbollah want to stay in Syria. We’re not as foolish as the superpowers. We don’t want permanent bases in Syria. We’re trying to help Syria strengthen itself, just like we’re doing in Iraq through the Popular Mobilisation Units.

Intentions notwithstanding, the question is how to persuade Iran, and Israel, to pursue stability and prevent a new conflagration in Syria. As with south-west Syria, Russia remains best placed to broker a deal, clarifying red lines and refereeing disagreements, which it will probably need to do to achieve the basic stability necessary for protecting the regime while drawing down its presence in the country. Basic rules of the military game might include:

  • Theatre of operations. What happens in Syria, stays in Syria and what happens outside of Syria, stays out of Syria. In particular, Iran, Israel and Hizbollah should prevent local clashes in Syria from spreading to other theatres, and from allowing clashes that may erupt elsewhere (for example Lebanon) from spreading to Syria.

  • Military infrastructure. Most of Israel’s sensitivities concern major military infrastructure – a naval port, an airport, an IRGC base and precision missile production facilities for Hizbollah – which are relatively easy to target and whose destruction by Israeli strikes Russia has demonstrated willingness to tolerate. Indeed, it seems easier for Moscow to let Israel constrain Iran’s presence in Syria than to do the constraining itself. Moscow should be clear with Tehran that it is not going to change course but that it will help Tehran better protect many of its interests in Syria so long as it does not pursue these major military infrastructure projects.

  • Personnel. Israel’s red lines regarding fighting forces will be much more difficult to maintain. Were Iran-backed militia forces to integrate further within Syria’s military and security structures, as some Syrian militia already reportedly have and as Tehran has called on others to do, or to simply don their uniforms, they will be harder for Israel to discern and, even if Israel has intelligence, risky to strike. Israeli officials fear that this reality could mean that integral parts of the Syrian army in effect would answer directly to Tehran. As the war subsides, the Syrian state probably will gradually exert more control, though Tehran, as it has elsewhere, likely will continue to find proxies. Russia and Iran seem to differ on this matter, with the former prioritising a centralised Syrian army and the latter seemingly keen on maintaining loyal forces. Disrupting Tehran’s network in Syria is likely to prove as difficult as elsewhere – in Lebanon and Iraq, and to a lesser degree in Yemen – and for Israel to make that a premise of a settlement is tantamount to saying there will not be one. Moscow should offer Israel its assistance to prevent the construction of the military infrastructure in Syria that it finds most threatening, the price for which is that Israel will not be able to extirpate Iran’s military presence, including those irregular forces that remain.

To some in Israel, this arrangement will smack of the balancing they are trying to escape. A deep sense of mistrust toward Moscow prevails in Israeli officialdom. But Russia is not only a constraint on Israel; it also could be a resource, the only power that, as an Israeli defence official who supports engaging Russia on this question put it, “has some leverage over them” (meaning Iran and its partners), and might be able to help Israel avoid an all-out war that it does not want to fight.


The Syrian civil war is still potent and there may be major battles ahead, but assuming present trends continue, the broad contours of its outcome are becoming clearer. Whether or not these contours come to define the parameters of an eventual intra-Syrian settlement, they are already defining the geography of the next Israeli-Hizbollah-Iranian war. Indeed, the uptick in Israeli strikes over the past months, especially against Iran-related targets, and more aggressive Syrian reactions, indicate that an incremental escalation already is occurring. There is still time for Russia to try to broker a set of understandings to prevent a confrontation, protecting both its investment in the regime and Syrian, Israeli and Lebanese lives.

(c) 2018 International Crisis Group

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