If Jeb Bush can't handle the most obvious questions of his candidacy, can he handle the presidency? My answer is at the bottom of this column, after some important background.

The scion of a family obsessed with Iraq, Bush was asked by FOX News' Megyn Kelly, "Knowing what we know now, would you have authorized the invasion?" Bush inexplicably said yes.

"I would have, and so would have Hillary Clinton, just to remind everybody, and so would have almost everybody that was confronted with the intelligence they got," said the former Florida governor, a GOP presidential contender.

"You don't think it was a mistake?" Kelly pressed.

"In retrospect, the intelligence that everybody saw, that the world saw, not just the United States, was faulty," Bush replied.

In other words, the weapons of mass destruction that sent the United States careening into war never existed, and yet—even in hindsight—Bush's position on invading Iraq is, "I would have."

English poet John Donne wrote, "No man is an island, entire of itself." John Donne didn't know Jeb Bush. Two-thirds of Americans, including half of all Republicans, don't think the war was worth the cost—nearly 4,500 American service personnel killed and $1.7 trillion spent through 2013, according to the Brookings Institution.

Conservative pundit Laura Ingraham said that no "sane human being" would invade Iraq in hindsight. Conservative author Byron York called the Kelly interview disastrous, noting that Bush's brother has a better rear view of Iraq.

Bush's view of the war is considerably less clear-eyed than that of his brother, former President George W. Bush, the man who ordered the invasion. In his memoir, Decision Points, W. wrestled with the dilemma of his decision to start a war on the basis of bad intelligence. Only W. did not call the intelligence "faulty," as Jeb had. W. called the intelligence "false."

"The reality was that I had sent American troops into combat based in large part on intelligence that proved false," George W. Bush wrote.

Even though W. still argued that the world is "undoubtedly safer" without Saddam Hussein, he knew the failure to find the weapons of mass destruction that he used to justify the invasion was "a massive blow to our credibility—my credibility—that would shake the confidence of the American people."

"I had a sickening feeling every time I thought about it," George W. Bush wrote. "I still do."

Sick feelings struck Team Jeb after the Kelly interview, and yet the candidate laid low for a day before telling another FOX News host that he had misinterpreted the question.

On Tuesday, Bush told Sean Hannity he would have made a different decision than his brother to invade Iraq in 2003 had he known what he does now about flawed intelligence. But he didn't say what that decision would have been.

"That's a hypothetical."

Alone on an island entire of itself—and the water's rising. Bush is drowning in denial. With the benefit of hindsight, he still can't say he'd stand up to the neocons and give us peace?

"I don't know," he told Hannity.

You might think the media is making too much of this. It's just a gaffe, the kind of thing that happens every day in presidential campaigns, which are a series of mistakes and surprises interrupted by an occasional planned success. You might be wrong.

To me, this feels like a window into Bush as a candidate and, perhaps, as a president.

First, it suggests he's not ready for the grind of a modern campaign. How can any presidential candidate—much less a Republican named Bush—not be prepared to explain exactly what went wrong in Iraq and how the lessons would be applied to his or her presidency?

Second, it suggests he's not the kind of leader who learns from past mistakes. That's a dangerous thing, because these were unforced errors that the next president must guard against. Invasion bias. Bad intelligence. Cherry-picked evidence. False and distorted claims from behind the presidential seal, the shallow mythologies of petal-strewing masses and postwar planning.

Despite his success as governor, despite the hard-earned experience and decency of his family, voters will ask whether this Bush is ripe for leadership in a world more complex than the one his brother inherited on September 11, 2001.

Would he project more strength than President Obama? Would he resist the war-first mentality of neocons? Would he benefit from the positives and negatives of the past two presidents and start rebuilding trust in the presidency?

My answer is as tentative as his: I don't know.

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