To me that doesn't seem ironic at all, and in fact morally (if not necessarily legally) consistent. They're trying to prevent nuclear militarization in Iran, and in this case doing so in a non-violent manner, specifically avoiding further "banging the drums of war."

I see no great evidence that the international community of today sets great stock by treaties, either, at least not much past about five minutes after the signing ceremony ends. "Paranoia" about the UN is an effect of this underlying problem, not the cause. Nor am I even remotely convinced that "Bush did it!"; flouting of UN convention and treaties goes back a lot farther than that and it takes a very narrow view of history to somehow lay it at the feet of any one party, or even "the West" in general.