What would it take to get the UN on board?

Great! Wondeful! You want to run the show? You pay the bill then! It is the height of arrogance to expect others to pay for your imperialist campaigns.

Right back where we started? Where was that exactly? You mean with Saddam Hussein 45 minutes away from threatening the entire western hemisphere with his arms of mass destruction? Or where the crime rate in Iraq was a fraction of what it is now? Where people there had electricity and running water? Where they had not been invaded and ocupied by a foreign army? Where many of those now dead were alive? Yes, I guess it would be rather awful to return to that, wouldn’t it?

Just to add to sailors points. Actually also the US are in a much worse situation than before, not only the Iraqis. You just created a whole new breeding ground for terrorists - nicely equipped with the weapons of a dissapeared army.