It depends on who you talked to at the time, I guess. WMD were indeed the initial justification; however, when various U.N. investigations failed to find much

It depends on who you talked to at the time, I guess. WMD were indeed the initial justification; however, when various U.N. investigations failed to find much in the way of evidence for WMD development -- other than a possible mobile chemical lab which may or may not have been used for WMD development IIRC -- the WMD justification came under heavy criticism by those who were following the progress. The WMD reasoning in fact came under international criticism before we officially breached the Iraqi border. I distinctly recall this because this situation was what prompted my research and essay at the time. The U.S. had mounted large forces on Iraq borders and other points in the area, and I guessed that there was no way the U.S. administration would then simply recall of those forces. They were there, so they had to do something. So, to counter the weakening of the WMD case, the case for human rights protection started making the rounds in mainstream media and talk radio. Suddenly the case wasn't that Saddam might be able to harm the U.S., it was that Saddam was a bad guy and we were going in there to do good things for the population that he was oppressing. And that worked long enough to roll the troops in, destroy some cities, topple a statue, and find the guy hiding in a hole.