I think the larger motive for the war in Iraq is to change the Middle East. Iraq was the easiest target. Iran probably is more important, but I think we felt Iran might change on it's own.
Many claim Iraq is a huge mistake, and if all Ben Laden and the Islamo-fascists have up their sleeve is 911-type of attacks, they could have a point.
If Islamo-fascists really are working and have a good chance of obtaining WMDs and can launch them, such as nukes, then it probably is worth the risk.
Without knowing the risks, it's a judgment call on the president's part. If Al Qaeda has nukes, then we may well not be aggressive enough.
In some respects, I think Bush's mistake was to take so long to attack Iraq. Had he moved against Saddam right after 911, it would have gone over better politically around the world.
I also think we have moved too slow to call elections and did not have a quick enough plan. In general, I think our problem is we are too slow. For example, we could have had a plan for an interim Iraq already drawn up to be implemented for 2-5 years, and let the new Iraqi Congress sort things out, and not provide so much of the security needs. If civil war erupted, we could then have a situation where one side asks for our help and so we agree to assist if they accept certain conditions.
Basically, I sort of think we don't play hardball enough with this area of the world.
I also probably would have advocated targetting Hamas, Islamic Jihad and all the rest after 911, and cleaned out Lebanon and toppled Syria first.
Maybe what we should have done is told Syria, Iran, and Iraq that they must cease all terror activities within 48 hours or we'll bomb the heck out of them until they do, and never send in large ground troops and don't help them rebuild and take a more punitive approach to ending their WMDs programs.