It is important to discuss the Iraq War from a Catholic just war perspective.
In my opinion, it is a just war.
Here is the definition of just war from the Catechism:
"2309 The strict conditions for legitimate defense by military force require rigorous consideration. the gravity of such a decision makes it subject to rigorous conditions of moral legitimacy. At one and the same time:
"- the damage inflicted by the aggressor on the nation or community of nations must be lasting, grave, and certain;
"- all other means of putting an end to it must have been shown to be impractical or ineffective;
"- there must be serious prospects of success;
"- the use of arms must not produce evils and disorders graver than the evil to be eliminated. The power of modem means of destruction weighs very heavily in evaluating this condition.
"These are the traditional elements enumerated in what is called the "just war" doctrine.
"The evaluation of these conditions for moral legitimacy belongs to the prudential judgment of those who have responsibility for the common good." (Vatican Website Catechism)
Here, in my opinion, is the response to that definition from the perspective of the war in Iraq.
The damage inflicted on our nation by the terrorist attack on the World Trade Center and the killing of thousands of innocent people, was lasting, grave, and certain.
Virtually all attempts to defeat terrorism throughout history have generally met with failure.
Attacking terror-supporting states like Afghanistan and Iraq, where terrorism has shown potent growth, with the long-range goal of creating a democratic society where tyranny once ruled, has a serious chance of succeeding.
The care of the use of arms which US troops have generally demonstrated has not produced evils or disorders graver than that which they seek to eliminate.