Isn't the use of the UN now simply an extension of what began as containment of Iraq via the UN 12 years ago? Because 12 years ago, we rescued a country without being directly attacked ourselves. I see this as a special circumstance of unfinished business that began multilaterally.
I could be wrong but I think Bush would never allow the UN to stand in the way of our own security and I think he's just about to prove it. I will admit, however, that I find the polls which demonstrate the majority of US citizens wanting UN approval to be frustrating. That will quickly dissipate after the next terrorist attack on our soil, however.