Some time before the war, the rest of the world noticed that the US was sending huge numbers of troops to the middle-east, preparing for war. Commentators understood two things: moving that many people and not invading Iraq would be very humiliating to the president; there was the season becoming less favorable to such a motion and it "needed" to be done fast.
However, the rest of the world understands that:
There is nothing worse than starting a war.
Wars have unpredictable consequences. The one who starts it could actually lose it. Wars provoke a huge number of deaths, and destruction.
There is one thing worse than starting a war: starting it for no good reason.
It's shameful Bush could convince so many it had to be done.