It looks increasingly likely that the United States, in conjunction with key allies, has decided to launch a limited military strike in the coming days to punish Syria for its apparent use of chemical weapons on August 21.
But U.S. President Barack Obama has also made it clear that he seeks to fulfill that goal without destroying the regime of Syrian President Bashar Assad, killing more innocent people, or sparking further regional escalation of the war.
While the United States has considerable military assets at its disposal, including ships in the region carrying scores of Tomahawk Land Attack Missiles (the likely stand-off weapon of choice), it is a challenge to calibrate the response just right. Too little force could have little effect, while too much could backfire.
The United States is not alone in this delicate balancing act. Assad, too, must carefully weigh his options as he ponders how he can respond to an anticipated U.S. strike without unleashing the wrath of the U.S. military and, as a result, jeopardizing his own survival.
Predicting Assad's response requires, in part, an understanding of the reason for his use of chemical weapons in the first place. Was it a step taken out of frustration or desperation? If the regime believes it needs to maintain a chemical weapons option it might be more inclined to respond. Conversely, was it a misstep, possibly reflecting divisions within the regime or poor command and control? In that case, retaliation might be less likely.
Assad's response will depend, perhaps to an even greater degree, on the nature of U.S. action and how he perceives U.S. strategy and intentions. Is a strike seen as merely symbolic? Substantive but limited? Or is it part of a new effort to overthrow the regime? A panicky regime that feels its survival is at risk is more likely to miscalculate or escalate. So too, conversely, is an overconfident one that believes an attack is little more than a slap on the wrist indicating weak U.S. and international resolve.
To reduce the risk of escalation, Obama has publicly telegraphed his intentions to Assad, making it clear that the U.S. goal is not to topple the regime. A similar message has likely been passed on to Syria's key allies, Russia and Iran.
As careful as both sides might be to calibrate action and response, developments can always spin out of control. Assad knows the "law of unintended consequences" well from earlier in his presidency: in 2005 Hezbollah's suspected assassination of former Lebanese Prime Minister Rafiq Hariri ultimately resulted in Syrian troops being forced to leave that country. In 2007 Syrian efforts to develop a covert nuclear capacity ended when Israel bombed the suspected reactor site. In 2011 efforts to crush largely peaceful protests sparked the current bloody civil war. This month's use of chemical weapons is another action for which the consequences — an impending U.S. military attack — were almost certainly not those that Syrian officials intended.
Moreover, in the fog and friction of war intelligence is imperfect and bombs and missiles don't always end up in the right place. Given the deaths of hundreds of civilians when the United States bombed the Amiriyah shelter in Baghdad in 1991 as well as the accidental bombing of the Chinese Embassy in Belgrade in 1999, American targeteers had better be very sure they know what not to hit in Damascus this time around. If a U.S. attack results in high Syrian civilian casualties or costs the lives of key regime figures, Assad might find himself under greater pressure to respond.
When and if the U.S. launches its attacks (likely targeting command and control centers, airfields, and strategic weapons and delivery systems), Assad might well do very little beyond issuing rhetorical condemnations. However, he will still have several possible retaliatory options that the United States and its allies will need to consider:
While very unlikely, if the Syrian leader believed that the end was near he could attack neighboring countries with a barrage of surface-to-surface missiles tipped with chemical warheads. Syria has a large, dispersed and somewhat hardened strategic chemical weapons arsenal that might well survive a first hit by the U.S. military. If Syria's target were Israel, this would invite swift and decisive Israeli retaliation, but the damage would already have been done. While Israel's missile defenses are more robust than any in the world, no such system is perfect. Jordan and Turkey are at risk, too. The former has hosted up to a thousand U.S. troops since June, including Patriot missile systems, fighter aircraft, and related support, command, control and communications personnel and systems. Turkey currently has Patriot missile batteries deployed from fellow NATO members Germany and the Netherlands. All of these Patriot systems are the PAC-3 variant able to intercept ballistic missiles, and their presence underscores the understandable nervousness of U.S. regional allies.
Assad could attack U.S. allies with conventional means. Such a strategy would have limited effects and would be almost self-defeating, however, because most U.S. allies are (especially with U.S. assistance) capable of protecting themselves from Syria's war-ravaged forces.
Aware of his limited conventional capabilities, Assad might try to drag his allies into a war with Israel. While Hezbollah already has thousands of men in Syria fighting alongside government forces, attacking Israel directly would risk another 2006-style war in Lebanon. Furthermore, Hezbollah's zeal and eagerness to fight Israel notwithstanding, the organization is in a politically sensitive position in Lebanon at the moment, a condition that would likely further deter it from opening two large-scale military fronts simultaneously. Given its long-term investment in Hezbollah, Iran would be equally unlikely to see its Lebanese ally dragged into a damaging fight with Israel at this juncture.
Some Iranian lawmakers have suggested that Iran would retaliate against Israel directly if Syria is attacked, but neither Iran's supreme leader nor the country's president has issued similar statements. This doesn't categorically guarantee that Iran will remain on the sidelines — in theory Iran could decide to attack U.S. assets in the Gulf — but this is extremely unlikely given the huge risks and consequences of such an action.
Assad could resort to covertly supporting terrorist attacks against neighboring states, or against U.S. targets in the Middle East or elsewhere. This is the least costly and most likely retaliatory option for Assad. However, it is not clear that Syria has much current capacity to organize such attacks, and might instead find it necessary to rely on Iranian or Hezbollah assistance. The 2012 bombing of a tourist bus in Burgas, Bulgaria — an act for which Hezbollah was ultimately blamed, and which led to European Union measures against the group — shows that even carefully planned operations can go wrong or backfire.
Assad could escalate domestically and pound rebel-controlled areas even harder to show that he is not intimidated. He would be smart not to use chemical weapons again, but even conventional escalation that results in heavy civilian casualties — a more prominent use of surface-to-surface missiles, for example — carries the risk of spurring a U.S. reaction. It is also doubtful how much ability the Syrian army has to step up the pace of its war-fighting.
All signs from Washington so far indicate that the U.S. strike will be limited. And Obama's declared Syria policy has not changed; it still seeks a political settlement between the government and the (still divided) opposition. The hope is that with the recent massive shipment of ammunition and light weapons from the Turkish border to the Syrian rebels and with the likely U.S. strike, the Syrian opposition will receive the help it needs to go to the negotiating table in Geneva with its morale boosted and its bargaining position strengthened (again, assuming it unifies and gets its act together). However, don't be surprised if the rebels, angered by the chemical attack and emboldened by a U.S. strike, harden their positions. Also, don't expect restraint from hard-line jihadist elements affiliated with al-Qaida either. They too will see an incentive to push even harder to topple Assad.
Saab is the executive director and head of research of the Institute for Near East and Gulf Military Analysis (INEGMA) North America. Brynen is a professor of Middle East politics and security at McGill University.