On September 17, will President Obama be explaining to the UN General Assembly why the US acted alone to respond to Syrian atrocities when the UN would not, or will he be chastising the UN for a lack of action, once again, to defend helpless citizens of Syria?
President Obama confronts a dilemma in dealing with the UN. He appears committed to military action in response to the apparent use of CW by Damascus. But, the UN process will not explicitly validate a military action—certainly not in the Security Council where Russia and China have vetoes.

This stasis occurs despite a trend of UN standards and precedents of justifying outside intervention when a sovereign government assails or fails to protect, its own population.
US UN Ambassador Susan Rice (now national security advisor) carefully worked this “responsibility to protect” standard in Libya. UN Resolutions 1970 and 1974, which Russia supported, embodied this standard. The failure to protect was seen as sufficient for outside military intervention. Ambassador Rice and others (including Kofi Annan) have been trying to build a legal framework so the international community can, indeed, would be obligated to act in the face of genocides and other horrors like Rwanda, Kosova, Darfur, etc.
But now the UN is viewed in Washington as a roadblock or at least a speed bump—much the way George Bush viewed it in 2002. President Bush said on September 12, 2002, “All the world now faces a test, and the United Nations a difficult and defining moment. Are Security Council resolutions to be honored and enforced, or cast aside without consequence? Will the United Nations serve the purpose of its founding, or will it be irrelevant?“

Will President Obama allow the weapons inspection process play out? This could add weeks of waiting for the results of laboratory analysis of samples taken. Moreover, the outcome is not 100% certain. It could muddy the waters with conclusions that CW was used—possibly with victims showing exposure on both sides. If is quite possible that some samples taken from Syrian soldiers could show evidence of nerve agent exposure—Russia (especially FM Lavrov.
What if the preponderance of an attack was conducted by the regime, but there were isolated cases of rebel use of even small inefficient amounts of CW?
What if the US intelligence suggests that there was a confused command structure that was unclear about who ordered the use? Or that implied that Bashir did not know of the attacks?
When President Obama addresses the UN General Assembly in a couple weeks, does he want to be justifying a unilateral attack on Syria not premised on protecting US security, but on humanitarian grounds? And then the evidence goes wobbly? (Recall Secretary Colin Powell’s performance in the UN Security Council portraying the evidence of Saddam’s WMD programs which melted away afterwards.)
Or does President Obama want to be chastising the UN for once again not acting in the face of yet another horrendous act by a government against its own people?
Given the range of uncertainties, and the potential for the US intelligence to be wobbly (and of course leaking) on such questions, on the surface, there seems ample cause for caution, at least for a couple of weeks. The UK parliament, in spite of a strong intelligence assessment from their Joint Intelligence Committee asserting multiple uses of CW by Damascus, seems to have opted for waiting this out.