Uh... Congress voted to approve the war along with all the UN resolutions that were approved. You're also forgetting the other Nations that joined in. You mentioned Bush but you left out all the Democrats that also voted for the war. Wouldn't that make Congress just as guilty?
Maybe we should go back and investigate the war in Vietnam, Germany and Japan too?
We killed a butt load of terrorists in Iraq and that's good enough for me. My only regret is we didn't kill more.