With his well-meaning effort to draw a red line around the use of chemical weapons, U.S. President Barack Obama seems to have painted himself into a corner in Syria. The wisdom of making public threats can certainly be questioned (contrast Obama’s public pronouncement to Secretary of State James Baker’s private warning on the eve of the Gulf War that Saddam Hussein should not use chemical weapons, which was ultimately successful). But the same goes for the oft-proclaimed need to follow up on public threats to protect credibility. Whether credibility matters forms the crux of the current debate about U.S. involvement in Syria -- an issue that’s almost beside the point if the official U.S. goal is to uphold the international taboo on chemical weapons use. What’s really at stake is whether there is legal precedent for such an attack (no); whether attacking could do more harm than good, including to international law (it might); and whether that taboo would weaken if the United States doesn’t attack Syria (perhaps not).

ILLEGAL AND LEGITIMATE

If U.S. claims are correct, Syrian President Bashar al-Assad has violated the near-universally accepted international norm against using chemical weapons. Although Syria is not a party to the Chemical Weapons Convention, it is a party to the Geneva Protocol of 1925. That protocol forbids its signatories to use asphyxiating gas on one another (without explicitly banning its use against a non-party) although, at the same time, demands its members’ consent that the prohibition on asphyxiating gases be universally binding. Unfortunately, the protocol contains no mention of how its provisions might be enforced. (This is not unusual for a treaty of that time, particularly one relating to disarmament.) Enforcement decisions are made by the UN Security Council, which must determine whether Syria’s infraction constitutes a threat to international peace and security. If it does, the Security Council must also specify the appropriate response. Possible measures include rhetorical condemnation; calls for Syria to join the Chemical Weapons Convention (a stricter agreement banning even the possession of chemical weapons); and sanctions, ranging from an arms embargo to economic and diplomatic restrictions.

The Security Council could also authorize armed intervention. But in its 67-year history, it has never once done so for the expressed purpose of enforcing compliance with disarmament obligations. The council did authorize intrusive inspections and sanctions against Iraq after its defeat in the Gulf War of 1990–91. Yet since the latter ended in a humanitarian disaster for Iraqis and a public relations disaster for the United States, particularly in the Middle East, the Security Council would likely think carefully before considering even much more carefully targeted sanctions this time around.

Absent a hawkish UN response to Assad’s use of chemical weapons -- which, given continued Russian support of Syria, seems unlikely -- individual nations could decide to strike alone or as part of a coalition, but doing so would, in many cases, run them afoul of their own UN obligations. The U.S. and British bombing of Iraq in December 1998 was ostensibly meant to enforce Iraq’s WMD obligations in light of the withdrawal of UN inspectors from the country. But the operation included numerous other targets, and was not widely perceived as a legitimate enforcement action. Further, throughout 2002 and 2003, the George W. Bush administration argued that Iraq’s violations of UN resolutions mandating inspections of its WMD capabilities provided legal warrant for an attack. In the absence of a Security Council agreement, though, such claims lacked legitimacy.

This situation bears some parallels to the dilemma of the 1998 Kosovo intervention, which was undertaken by NATO without UN authorization. Later, the intervention was famously judged by the Independent International Commission on Kosovo to be “illegal but legitimate.” In that case, though, there were additional mitigating circumstances: the intervention recouped some standing through efforts, after the fact, to push forward the Responsibility to Protect (R2P) doctrine, whose proponents have attempted to include humanitarian intervention as a permissible legal ground for the use of force. That effort is a work in progress, at best. And, anyway, it wouldn’t really apply to the Syria case, since more relevant laws -- namely the Geneva protocol and the Chemical Weapons Convention -- already exist.

RIGHT AND WRONG

That leads, then, to another question: Even if the Obama administration would not be legally right to go it alone or with an ad hoc coalition in Syria, would it be morally right? To answer that, one must consider whether such an attack would result in other UN members taking their obligations about the use of force less seriously, and then weigh that against how important a strike would be in ensuring the upholding of the chemical weapons taboo.

An unauthorized attack would represent a step backward for the international legal regime governing the use of force -- and one that would come disappointingly soon after the recent step forward of the UN authorization of the intervention against Libya (which was not without controversy). And the United States (and any nations that join it) should not have to take responsibility for international norms; that is a burden that should ideally be borne by all members of the UN Security Council. If the report of the UN inspection team buttresses U.S. claims that a Syrian chemical attack has killed more than 1,400 people, all members of the Security Council should feel obliged to authorize action. The United States’ proper role is thus to push for the most robust response with the broadest international legitimacy possible. Russia’s refusal to accept U.S. evidence about the attack to date seems to leave that option nearly off the table, although Russia would have to explain itself at least if the independent UN report provides more ammunition for holding the Syrian regime responsible; Putin recently indicated an openness to Security Council action if Russia was convinced.

One could forgive the cynic for pointing out that, despite all the focus on the alleged perils of violating the legal regime governing the use of force, those rules have been frequently transgressed; the reality is that the United States has been the chief violator in a crowded field of abusers. In that sense, a limited strike by the United States would hardly do novel and definitive damage, certainly dramatically less than operations such as the 2003 war in Iraq.

NO WAR, NO PROBLEM

Plenty of observers would interpret any U.S. attack in the region as being motivated by less than morally agreeable objectives, which means that an attack might not buttress the chemical weapons taboo. At the same time, a failure to attack Syria need not signal a decisive blow to the norm against chemical weapons use, particularly if moral entrepreneurs committed to its enforcement doggedly pursue diplomatic efforts to ensure that those responsible pay a price. Recall that this is the first violation of the taboo in some 25 years -- not a bad track record by the standard of any social norm. There is not a long line of would-be chemical weapons users lying in wait. Only seven states in the world remain outside the Chemical Weapons Convention of 1993, which was developed in the wake of the world’s failure to deal with Iraq’s chemical weapons in the 1980s. The tremendous global outcry of horror at Syria’s alleged use of chemical weapons means that, even short of the most extreme enforcement measures, it would take a peculiar leader to judge that he could follow suit without risking sanctions, military attack, or loss of legitimacy and isolation as the leader of a rogue state. Even Hitler, as I pointed out in a recent Washington Post interview, didn’t use them against allied cities or troops as a weapon of war (although he had no compunction against using them in concentration camps).

A military strike would represent the strongest possible enforcement of the taboo, and could be justifiable if it were within the bounds of just war criteria, but other measures could reinforce the taboo while forestalling any significant erosion of the international legal regime. The requirement for just cause would most strongly be met if an operation were carried out to blunt an imminent attack. The requirement for a reasonable chance of success is trickier: the dilemma is that, operationally, the longer diplomatic measures are allowed to run their course in a bid to gain legitimacy, the less chance a military attack likely has of working to effectively degrade Syria’s chemical weapons capability. Indeed, that window may have closed, although Obama himself has indicated that the success of the operation is not time sensitive. In that regard, there might also be moral value to a more general attack designed to punish Syria for its crimes against its people. That, however, has to be weighed against the damage to the rules governing the use of force.

Absent a perfect storm of moral opportunity, a long-term commitment to pressing for Syrian ascension to the Chemical Weapons Convention might best accommodate competing legal and moral imperatives. That convention contains far-reaching and intrusive provisions governing the use, possession, production, and trade of chemical weapons. All parties to the convention are subject to inspections by the Organization for the Prohibition of Chemical Weapons. Like the Geneva Protocol, the Chemical Weapons Convention does not explicitly stipulate its own enforcement mechanisms. Instead, it delegates any enforcement measures responding to “cases of particular gravity” to the United Nations. The fact is that, even though it is not a party to the convention, Syria did allow a UN team to enter Syria. Incomprehensibly, Damascus appears to have launched the major attack of August 21 just as the team was preparing to tour sites of other alleged attacks.

Particularly if the UN team’s findings point to Assad’s culpability, the Security Council should issue a resolution condemning the Syrian use of chemical weapons and strongly encouraging Syria to join the Chemical Weapons Convention. Assad would almost surely refuse, but any opposition group that succeeded him could be persuaded with continued diplomatic carrots and sticks. All that might seem like a pipe dream, but it is worth remembering that progress in global arms control and disarmament has followed such paths. Libya joined the Chemical Weapons Convention in 2004 in an attempt by former leader Muammar al-Qaddafi to rehabilitate the country’s international image, and the new postwar regime in Iraq joined in 2009; similarly, new regimes in Serbia and Afghanistan joined the land mines convention as they took power in bids to bolster their standing as good international citizens.

Leaders of rogue states have not fared well over the last decade or two. This episode has provoked international condemnation that has already reinforced the norm against use of chemical weapons. That progress can continue, even in the absence of a military strike.