Why does the use of chemical weapons justify international retribution with military force, in a way that two years of brutal repression with tanks and planes does not? And where in international law is the legal "cover" for such action?
If the Obama administration is planning for limited military strikes against Syria to hold the regime "accountable" -- in the words of senior officials -- for using chemical weapons, it is probably drafting some answers to those questions.
The president put it like this in his CNN interview last week: "If the U.S. goes in and attacks another country without a U.N. mandate and without clear evidence that can be presented, then there are questions in terms of whether international law supports it, do we have the coalition to make it work?"
Forcibly intervening for humanitarian reasons, to protect innocents from appalling suffering, is a noble concept, one that would draw on the moral outrage felt around the world. The thrust of President Obama's argument has always been humanitarian: that using chemical weapons, which are horrendous and indiscriminate by nature, would cross a "red line."
U.S. Secretary of State John Kerry amplified the argument Monday when he said, "President Obama believes there must be accountability for those who would use the world's most heinous weapons against the world's most vulnerable people."
In other words, the "strictly legal" should not be allowed to cancel out a legitimate and necessary course of action, even if international law provides no clear support for intervention on humanitarian grounds.
France, the UK, Turkey and Germany have all signaled support for such an approach. "The international community must act should the use of such weapons be confirmed," says German Foreign Minister Guido Westerwelle.
But in this instance, the international community is likely to mean NATO, not the United Nations, and that would carry much less weight in international law.
Pre-emptive force to protect U.S. allies
Ashley Deeks, who worked in the Legal Adviser's Office at the State Department for a decade, wrote on the Lawfare blog that the U.S. "might believe that a Syrian use of chemical weapons is likely to affect neighboring (and friendly) states such as Turkey and Jordan," depending on where they were used.
Daniel Bethlehem, who held a similar position at the UK Foreign Office, adds that the request by Turkey for Patriot missile batteries last year "suggests the possibility of a collective self-defence rationale for military intervention to address such a threat."
This argument for "anticipatory" self-defense, to take out something before it is used against you or your allies, is gaining favor in light of the nuclear programs being developed by Iran and North Korea and the unpredictable nature of the global terrorist threat. After 9/11, the Bush administration fashioned a national security strategy that included and justified the use of pre-emptive force.
"We must be prepared to stop rogue states and their terrorist clients before they are able to threaten or use weapons of mass destruction against the United States and our allies and friends," the 2002 document said.
Obama hinted at this argument in an interview with CNN last week.
"When you start seeing chemical weapons used on a large scale ... that starts getting to some core national interests that the United States has, both in terms of us making sure that weapons of mass destruction are not proliferating, as well as needing to protect our allies, our bases in the region."
Intervening in Kosovo
Some observers have invoked the precedent of NATO's 78 days of bombardment against Serbian forces in Kosovo and in Serbia in 1999. The alliance argued that as a regional grouping, it had the right to intervene in Kosovo to prevent a humanitarian catastrophe and protect the stability of Serbia's neighbors.
"We cannot stand by and let the Serbs crack down again on the Kosovar Albanians," said then-U.S. State Department spokesman Jamie Rubin. "We believe that is a substantial and legitimate grounds for action internationally."
Even so, U.S. and NATO officials, from then-Secretary of State Madeleine Albright down, argued later that Kosovo should not be seen as a precedent. The U.S. State Department's legal adviser at the time, Michael Mathison, talked about a "unique combination of a number of factors" and insisted the U.S. and its allies did not see humanitarian intervention as the legal basis for the Kosovo campaign.
In the case of Syria, neither the United Nations charter nor the Security Council is likely to offer much cover for intervention. The charter forbids the "use of force against the territorial integrity or political independence of any state" but allows for the use of force in self-defense. Article 51 reads, in part: "Nothing in the present Charter shall impair the inherent right of individual or collective self-defence if an armed attack occurs against a Member of the United Nations."