I was studying politics at university at the time - it was insuferable.
The turnout to the protest from our end was great. "A free shuttle bus down to London and back?! Sign me up... there's loads of shopping I need to do" seemed to be the prevailing attitude from what I remember. Still, the militant unions didn't mind, they could put out a press release saying that the transport they laid on was packed to the hilt and artificially bump up the numbers of those 'attending' the protest. I assume this approach was replicated at universities across the land.
I contested at the time that the Iraq war was a humanitarian mission, and I maintain that position today. As democracy flourishes in Iraq and throughout the Middle East, it seems I was vindicated beyond dispute.