The race between Blair and Blix
I know these things are very bureaucratic and tiresome but it's worth re-reading what it was exactly that MPs were asked to vote on when they voted for the Iraq war. It was that Saddam Hussein's regime was in breach of a UN resolution; and, because it hadn't been possible to secure a second authorisation from the UN, the UK government could use 'any means necessary' to remove Iraq's weapons of mass destruction. (see below).
Blix (and Chilcot) are quite entitled to say now that a) the WMD hadn't been found and b) with more time, they could prove this. The point is that what Blair and Bush really feared by this point was that Blix would NOT find WMDs, in which case, the only case for war was 'regime change', and that on its own would be even harder to win at the UN or at home in the UK or US.
Those of us who took part in all the demos and lead-up, I think we can remember all this...but it tends to get submerged under much more stuff. I can remember thinking, this is a race: between Blix NOT finding WMDs and Blair getting a vote through on going to war to 'eliminate' these non-existent WMDs.
There was no other reason for getting Blix et al being pulled out of Iraq. The Blair-Bush axis wanted war, they were going to do all it took to get war, they got war.
British Parliamentary approval for the invasion of Iraq was given by the elected members of the British House of Commons to Tony Blair's government on the eve of the 2003 invasion of Iraq, in a series of two votes, on 18 March 2003.