At the opening of last night's The Daily Show, when Jon Stewart made an (intentionally) awful joke about spotted dick in honour of the programme's British guest, you could imagine Tony Blair sitting in the green room, suddenly thinking he'd made a terrible, terrible mistake in agreeing to appear.

He hadn't, though. It's true that Stewart is an outspoken critic of the Iraq war , the defining event of Blair's premiership, and the format of his influential show allows him to sting with mockery and false chumminess; the live studio audience, meanwhile, has definitely been known to boo. But Blair, or his advisers, had read the state of debate on Iraq in the US correctly: by showing up at all, he'd already shot past the war's American architects in Stewart's estimation. And by repeatedly stressing that he accepted the right of others to take a different position — "I never took the view that people who disagreed with it were stupid or had bad intentions," he said — he guaranteed his warm reception.

At one point, after making an anti-war point, Stewart seemed embarrassed by the volume of the audience's cheering. ("I just want to tell you," he told Blair, in a stage whisper, "the tickets are free".) The former prime minister exploited a flaw in The Daily Show concept, too: answer a difficult question earnestly, even boringly, and you can be sure that Stewart will be forced to change the subject sooner, in order to keep things funny.

Blair had barely begun to explain his relationship with George Bush when Stewart chipped in: "Did [Bush] understand the time difference? Or would he call you up, and it would be four in the morning, and he'd be, like, 'Tony, you gotta turn on Channel Four! There's a snake eating an egg!" It was one of the evening's funniest lines — almost all of the funny lines came from Stewart, of course — but it also stopped a potentially valuable line of questioning.



By the end, Stewart had all but lost the will to question Blair's argument that the Iraq war was vital in combating terrorism around the world. "Look, this is going to take us all night, and it's not pleasant," he said. "You know, here's the thing I want to tell you: I'm delighted to even get an opportunity to talk to you, and I appreciate your patience — even discussing all this with me, because I think it's very kind of you... Something I appreciate is, I live in this country, and I've asked our president to actually, many, many times come and explain this to me, and he doesn't feel like it."

"Do you want me to speak to him about it?" Blair replied, making his first real joke of the night. And everyone laughed and cheered, and the two men shook hands, and that was that. It was all a bit underwhelming. But perhaps it says something good about the Daily Show — or bad about the rest of the American television news media — that anyone might ever have expected a comedy talkshow to penetrate deeply into a topic such as Blair's motivations for going to war in Iraq.

• Watch the show air in the UK on More4 tonight at 8.30pm.