Parliament voted for it because they thought Saddam had WNDs, They were told lies like the rest of us.So yes, the dossier was sexed up, that isn't to say that Blair didn't believe the essence of it to be true, that Saddam was a danger, and ultimately if the people wanted us to go to war or not was technically not relevant, parliament decided to go to war, and we elected them to make decisions like that. That's our system, regardless if we agree with it.
The threat of WMDs was the premise for war.
Blair had access to all of the Intel. IMO he has NO defence and I hold him personally responsible.