John Callender at Lies writes that many advocates of the battle in Iraq see our invasion as a direct result of 9/11. This is true. He goes on to say, however, that because there as been little evidence of a direct relationship between Saddam and al Qaeda (he might say no evidence) that this reasoning cannot be used to justify the invasion.
However, there can be no denying two facts:
1. Saddam did have direct relations with other terrorist groups, such as Hamas, Islamic Jihad, and Hezbollah. He funded terrorist attacks within Israel, and facilitated these groups' operations all around the world.
2. Saddam's oppression of the Iraqi people was a part of the vast swamp that encourages and contributes to the Arab Muslim terrorist mindset. If, as many leftists claim, such terrorism flourishes due to repressive dictators that the USA has propped up, eliminating one of those dictators directly addresses one of the "root causes" the leftists are so fond of.
Furthermore, don't forget that after the US entered WW2, our first step in Europe was to invade Morocco. Why would we do such a horrible thing? What did Morocco do to us? For strategic reasons, Morocco was a sensible place to start our counter-offensive against the Germans in North Africa. Similarly, Iraq was the low-hanging fruit among our enemies (and they were our avowed enemy); even if I concede a lack of direct connection between Saddam and al Qaeda, there's no shortage of indirect connections.
Even though different people had different motivations, they all led towards the same intent: topple Saddam Hussein. Some of those motivations may have been selfish, or logically flawed, or noble, or anything, but the cumulative effect of them was widespread and irresistable. Though different people may have had different reasons, everyone agreed on what had to be done, and so it was.
My own personal reasons are based on the overall War on Terror, and so I justify our battle in Iraq on those grounds. The liberation of the Iraqi people is an important step towards our victory in the greater war; not merely because I think everyone deserves to live free (although I do), but because until the Arab Muslim world is free we will continue to be in danger.
Update:
The post originally said "Monaco", but as SDB points out, I meant "Morocco". No wonder my Google search for the date we invaded Monaco turned up nothing.