It's hard to make small talk with someone responsible for the deaths of hundreds of thousands. So Ryan Tubridy began his first interview of the season with a discussion of former British prime minister Tony Blair's childhood holidays in Donegal. Iraq sat there like an elephant in the room. Even Blair looked uneasy. He was probably thinking: "Seriously, I started a war for no good reason, people aren't interested in my holidays."

Earlier in the week Blair returned to the limelight to promote his political memoirs, and was interviewed by the BBC's political pundit Andrew Marr. Marr had come out swinging from the start, but The Late Late Show is a different sort of a beast, designed to please all of the people all of the time and instinctively more interested in twinkly-eyed anecdote than political scoops.

Granted, Tubridy's opening gambit did seem designed to put Blair on the back foot. "I see you went with the tie in the end," he said, which seemed like a dig at the culture of cosmetic spin Blair established during his tenure at Downing Street, but was actually a reference to a real sartorial dilemma Blair was having about whether to dress casually or formally. Blair revealed that he'd borrowed the tie from someone in the backstage corridor.

A discussion of his Donegal holidays ensued. Then an anecdote about his slightly-bigoted Protestant Irish grandmother led to a discussion of the peace process. With Irish or UK politicians this amounts to "Tell me again why you are so brilliant" and Blair did his best to sound humble. He discussed the "cunning" of Bertie Ahern and how he controversially liked most of the participants in the process. This was followed by a story about his son's drunken GCSE night and an examination of whether he fancied Princess Di.

If it had been a horror film there would have been ominous music playing in the background. Then the storm broke. "What did you make of George W Bush?" asked Tubridy and Iraq was on the agenda. Tubridy didn't shy away from the hard questions although sometimes he seemed to push it for the sake of pushing it.

"Did you pray with him?" he asked.

"No," said Blair looking slightly annoyed.

"It's a legitimate question," said Tubridy.

"It would be if it hadn't been asked 10 times before and I hadn't said 'no' each time," said Blair.

All in all, Tubridy did well. Blair's justification for the war is complicated and involves repeatedly asserting that Saddam was in breach of UN guidelines even though no weapons of mass destruction were found. So it was cathartic to hear Tubridy cut through the gibberish to ask questions like: "Does your argument help you sleep at night?" or "Are you a war criminal?" or "Do you ever feel sometimes that perhaps you have blood on your hands?"

These are both cheap shots and legitimate questions. But Blair's basic defence was cobbled together whilst viewing the Gwyneth Paltrow vehicle Sliding Doors. Yes, he says, Iraq is a disaster with many people dead, but we have no way of knowing what would have happened if we hadn't invaded. So what's more interesting is not Blair's argument but his belief in it. He looks uncomfortable discussing funny stories and personal matters, but comes into his own on Iraq. His voice becomes angrier, his gaze intense and he gives no quarter. Tubridy can credibly attack but not penetrate that self-belief. I suppose that's Blair's life now: long stretches of nervous calm between bouts of defending his record.

Then Tubridy was asking less consequential questions about Blair's troubled relationship with Gordon Brown, his Catholicism and an incident at a French press conference. It was all a bit "tonight Matthew, I'm going to be defending my record in Iraq and then telling a funny story about the French". But that's The Late Late Show. If we don't want it we shouldn't vote for it.