Daily catch-up: 'the intelligence agencies' conclusion about Iraq was both reasonable and wrong'

The subject of Iraq has been raised again, by the reaction to Tony Blair saying the same as he has always said

Sir Menzies Campbell and I disagree about Tony Blair's restated apology in The Independent today. As the Mail on Sunday raised the subject on its front page yesterday, I draw your attention to another section of Superforecasting: The Art and Science of Prediction, the brilliant new book by Philip Tetlock and Dan Gardner.*

It deals with the failure of the US intelligence agencies to predict that Saddam Hussein had got rid of his weapons of mass destruction – "arguably the worst intelligent failure in modern history". Tetlock writes:

What went wrong? One explanation was that the intelligence community had caved to White House bullying. The intelligence had been politicised. But official investigations rejected that claim. So did Robert Jervis, a fact I find more compelling because Jervis has a four-decade track record of insightful, nonpartisan scholarship about intelligence. Jervis is the author of Why Intelligence Fails, which meticulously dissects both the failure of the intelligence community to foresee the Iranian revolution in 1979 – Jervis conducted a post mortem for the CIA that was classified for decades – and the false alarm on Saddam Hussein's WMDs. In the latter case, the intelligence community's conclusion was sincere, Jervis decided. And it was reasonable.

"But the conclusion wasn't reasonable," you may think. "It was wrong!" That reaction is totally understandable – but it too is wrong. Remember, the question is not, "Was the intelligence community's judgement correct?" It is, "Was the intelligence community's judgement reasonable?" Answering that question requires putting ourselves in the position of the people making the judgement at the time, which means looking at only the information available then, and that evidence was sufficient to lead virtually every major intelligence agency on the planet to suspect, with varying confidence, that Saddam was hiding something – not because they had glimpsed what he was hiding but because Saddam was acting like someone who was hiding something...

So the question, "Was the intelligence community's judgement reasonable?" is challenging. But it's a snap to answer, "Was the intelligence community's judgement correct?" ... A situation like that tempts us with a bait and switch: replace the tough question with the easy one, answer it, and then sincerely believe that we have answered the tough question.

This particular bait and switch – replacing "Was it a good decision?" with "Did it have a good outcome?" – is both popular and pernicious...

So it's not oxymoronic to conclude, as Robert Jervis did, that the intelligence community's conclusion was both reasonable and wrong.

However, Tetlock adds that Jervis does not let the intelligence agencies off the hook. "There were not only errors but correctable ones," Jervis wrote. The agencies probably wouldn't have reached a "fundamentally different conclusion" but they should have been "less certain". Tetlock comments that analysts know that intelligence always involves uncertainty, yet on Iraqi WMDs they "fell prey to hubris". The National Intelligence Estimate said, "Baghdad has chemical and biological weapons..." without qualifying this with an estimate of probability. "Post mortems even revealed that the intelligence community had never seriously explored the idea that it could be wrong," writes Tetlock. He quotes the presidential investigation of 2005: "Failing to conclude that Saddam had ended his banned weapons program is one thing – not even considering it as a possibility is another."

*I commented on it here, here and here.

• In my column in The Independent on Sunday I asked whether the tax credits disaster may have ended George Osborne's chances of succeeding David Cameron as prime minister – and secured Boris Johnson's.

• The Top 10 in The New Review, the Independent on Sunday magazine, was People Who Would Have Been Good On Twitter. As Rob Ford pointed out, Pepys would have been on Facebook a lot, with photos of his lunch.

• And finally, thanks to Glenny Rodge ‏for this:

"Doctor, doctor, I keep thinking I'm in the song 'Summer Nights'."

"Hm, tell me more."

"Wait, we haven't done the 'wella wella' bit yet."

"Get out."