You may find this hard to believe considering that I was in the Marine Corps, but I abhor violence. I also believe that most war can be prevented with proper diplomacy and problem solving.
Still, as a Centrist/Democrat who abhors war, I think going into Iraq was necessary. We're not talking about something the Bush family started, or personal vendettas. We're talking about Saddam practicing genocide, using WMD, attacking neighboring countries and supporting terrorists.
Iraq wasn't tied to Al Queada directly, but Saddam did finance terrorism. And whether people realize this or not, but by going into Iraq we also shifted the battleground on the war on terror. Osama Bin Laden said himself the battleground against the US is in Iraq now. Instead of terrorists striking the US on US soil, they are striking the US in Iraq. We're not fighting Saddam's remaining loyalists. We're fighting Al Quaeda members from Syria, Afghanistan, Pakistan, etc.