Donald Trump blamed George W. Bush for allowing the 9/11 attacks to happen Friday — but perhaps Bush’s best defense comes from one of the former president’s most vehement critics.

“When you talk about George Bush – I mean, say what you want, the World Trade Center came down during his time,” Trump said in an interview with Bloomberg Television.

After the host pushed back on the charge, Trump doubled down: “He was president, OK? Blame him or don’t blame him, but he was president. The World Trade Center came down during his reign.”

It is a fact, of course, that the 9/11 attacks occurred nine months into Bush’s presidency. There is also a strong case to be made that like Bill Clinton before him, Bush didn’t take the threat from Islamist terrorists as seriously as he should have upon assuming office.

But could Bush have prevented 9/11 if he acted more aggressively against terrorism at the beginning of his administration? According to one of his loudest and most expert critics, the answer is no.

Richard Clarke served as chief counter-terrorism adviser on the National Security Council at the beginning of the Bush administration. After leaving government in 2003, he became a vocal Bush administration critic, lambasting it for not heeding his warnings to take al-Qaida more seriously in the months leading up to the 9/11 attacks.

But take a look at what Clarke said under oath during his testimony before the 9/11 commission in 2004 when questioned by former Republican U.S. Sen. Slade Gorton, who was one of the 9/11 commissioners:

GORTON: Now, since my yellow light is on, at this point my final question will be this: Assuming that the recommendations that you made on January 25th of 2001, based on Delenda, based on Blue Sky, including aid to the Northern Alliance, which had been an agenda item at this point for two and a half years without any action, assuming that there had been more Predator reconnaissance missions, assuming that that had all been adopted say on January 26th, year 2001, is there the remotest chance that it would have prevented 9/11?

CLARKE: No.

GORTON: It just would have allowed our response, after 9/11, to be perhaps a little bit faster?

CLARKE: Well, the response would have begun before 9/11.

GORTON: Yes, but there was no recommendation, on your part or anyone else’s part, that we declare war and attempt to invade Afghanistan prior to 9/11?

CLARKE: That’s right.

So, yes, Trump is right that 9/11 happened while Bush was president. But even one of Bush’s most expert critics said that there wasn’t the “remotest chance” Bush could have prevented 9/11 by acting more aggressively against the terrorism threat in the first several months of his administration.

Now, it’s of course possible Clarke is wrong and Trump is right. And Clarke did later try to backtrack a bit from his testimony by saying perhaps the 9/11 plot could have been uncovered if the intelligence community acted competently. But for George W. Bush, it’s hard to do better than Clarke’s testimony under oath before the 9/11 Commission as a defense against The Donald’s charge.

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