We are in Iraq as a continuation of Gulf War I.  Saddam defied 17 UN Security Council resolutions.  If the corrupt French had not guaranteed they would keep the US from attacking, then Saddam would have backed down.  As it was, he felt secure with France and Russia in his hip pocket due to Oil For Food bribes and oil development deals, and he WAS slipping sanctions and he WAS denying UNï»¿ inspectors access to Iraq.  Go read 'The Bomb in my Garden' about reconstituting his weapons programs.