Yes, in all the ink spilled over the past few years, five potential motivations behind the Bushite invasion of Iraq stand out (I will exclude factors as being played for a complete fool by the Iranian agent Chalabi).
1. Weapons of mass destruction. No.
2. Saddam had links to Al Qaeda. An even greater no.
3. Promotion of democracy. Forget it, a desperate last-minute ploy.
4. To be a lesson to countries in a post 9/11 world: this is what happens if you cross the United States. I think this was indeed a major factor for both Bush and Cheney, and many on the right still laud this tactic, and point to the fact that Libya gave up its weapons program in the aftermath (ignoring the fact, of course, that Gadaffi was looking for a way out for more than ten years). But I think we can safely say that this was also a failure, creating unprecedented hatred for the United States in the world, and providing a fertile breeding ground for a new generation of bitter terrorists.
5. The flypaper theory-- America fights them there, so it's not necessary to fight them here. Ron Suskind claims that Bush was a big believer in this tactic, in the hope that Iraq would become a quagmire that would bring all the terrorists in the world out of the wordwork. There are a couple of problems with this of course. First, it assumes that the number of terrorists in the world is static, and will not multiply precisely in response to Bush's actions. Second, think about the morality of this for a moment. Bush is basically happy to destroy a whole country simply to create a convenient battleground.
In sum, think about the implications of these motivations in the context of just war theory. The first two, the ones with some case for justifying war were the very reasons that turned out to be false, and encased in a blanket of lies. The last two, in contrast, are deeply immoral reasons for going to war-- and it seems like these were the two motivations that most guided our illustrious Christian president George W. Bush, and his henchman from the dark side, Dick Cheney.