Meaningless arguments
As I pointed out in the post above, this entire argument is meaningless since there is no American course of action that would ever have been acceptable to the U.N. that would now require troops, money, and the rest.
To simplify:
U.N. approval = no war
War = no U.N. approval (what happened)
There is no action Bush or Blair could have taken that would have resulted in:
U.N. approval > war > U.N. assistance with war.
So what's the point? No matter what we could have done before, or can do now, the United States and its allies are stuck with the job and we might as well deal with it.
BTW, would love to know how "additional voices" deter terrorists. Are they like, really squeaky and annoying ones?