Someone said that Blair was the kind of guy who always wanted to be at the right parties, he had to be at the top table - hence he wanted to get in with the US. And also, I think, he thought it would be straightforward and relatively easy, rather than the shambles it turned out to be.
He had the whip hand having taken his party to victory twice having had Labour in the wilderness for so long. That, and there was the aura of a cult about him. It has never really dissipated, that sense the if the State says it is so, then it is so. The truth is what they say it is. Onwards and upwards!
He bangs on about how history will judge - words from someone who wants to delay judgement as long as he can. I have to say in those clips he looks smart but out of his depth, as most would be under those circumstances - but until then his career had moved forward without setbacks of any major kind, so he probably figured he'd got this.
On a facile note, his hair receded very oddly and suddenly it seemed - guess he's had a hair transplant since.