Realistically, if this had been the case when the USA and allies wanted to get a blessing on attacking Iraq and had failed to get it, I doubt that the result would have been any different.

If the UN had then passed a motion to help Iraq - what then? Any volunteers to get wiped out by the Americans? It's bad enough being their allies!

The UN is only there to give moral superiority to whichever country is being attacked by the major power. Those being attacked will get the same limp "support", a few speeches to decry the action, and that's about it unless countries want to help unilaterally.