"the UN did indeed decide that Iraq should disarm but it also decided on how this should be monitored and the US chose to ignore this."

But where do you draw the line?

Assume for a moment that Iraq did/does have the weapons. Was it OK that Saddam hid them, did not cooperate, threatened the scientists, bugged the meetings, etc,? While he was doing this, he was growing in power, killing and torturing, oppressing his people, stealing oil revenues to build palaces.

Assume for a moment he did NOT have them. Well, I don't see too many people complaining that he's gone, least of all the Iraqi people. Even France agrees the world is better without him. Sure they want us to leave, but that's because they want their country back after so many years! And they're enjoying their newfound freedom to protest.