(CNN) -- 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?"
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President has said that Syria's use of chemical weapons would cross a "red line"
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Administration might be asking: What justifies military action, and where's legal cover for it?
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International law provides no clear support for intervention on humanitarian grounds
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Syria is bound by the Geneva Gas Protocol, but does that cover internal conflict?
"Why should the @placeholder be willing to intervene if chemical weapons kill 1,000 civilians, but not if ordinary weapons kill tens of thousands?"