I've got fairminded friends who favored the war because they believed it would relieve the suffering of the Iraqi people. They pointed out, rightly enough, that the sanctions regime was causing great suffering among ordinary Iraqis, without compromising Saddam's hold on power. This was always the best argument in favor of the invasion (though perhaps a better argument in favor of simply ending the sanctions).
However, no matter how bad the sanctions regime was for the public health and welfare of ordinary Iraqis, it always seemed to me absurdly optimistic to think that Iraqis would be better off after being invaded and occupied by knee-jerk anti-statists. Part of my argument on this matter was that, as bad as things were in Iraq under the late Saddam regime, at least the situation was more or less stable, and that people had probably found as good an accomodation as possible with that situation. The inevitable chaos and uncertainty engendered by the overthrow of the old regime was bound to upset the delicate equilibria established by marginalized individuals.
Given all this reasoning as background, I wonder how my liberal hawk friends are feeling this morning as they read that acute malnutrition among young children in Iraq has nearly doubled since the United States invaded the country 20 months ago.