But then hindsight is not a straightforward luxury and if some felt that the UK govt were privy to intelligence reports regarding Saddam Hussein's intentions, then maybe some in the UK govt felt the same with regards to the Americans.
But is that excusable? Perhaps the best attitude to have taken was the same the British government took during the Vietnam conflict, i.e. tacit support rather than full-scale involvement. The Prime Minister at the time, Harold Wilson, was one of the more canny occupants in Downing Street's history and perhaps we needed such an individual at that time!
But this is academic, what is done is done and we must now redouble our efforts to try and redeem ourselves by helping restore Iraq to being a Democratic and peaceful nation that is a beacon to others within the Middle East.