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 Hizbo