Oh, those hands. Donald Trump holds them out, regards them, waves them for everyone in the gleaming conference room to see. How surreal is this? We are talking NATO, the Senkaku Islands, nuclear proliferation . . . and hands.

My hands are fine,” Trump says. “You know, my hands are normal. Slightly large, actually. In fact, I buy a slightly smaller than large glove, okay?”

Is this really happening? “Surreal” may not capture the utter weirdness of the moment. We are talking hand size — and other size — with the Republican front-runner. For president.

The topic, admittedly, has been broached not by Trump but by the otherwise cerebral editor of The Washington Post’s editorial page, Fred Hiatt. “You are smart and you went to a good school,” Hiatt says.

He is following up on Trump’s boilerplate assurances about his intellect, complete with reference to his MIT-professor uncle, “one of the brilliant people.” It’s not my place to interrupt, not too much, but I’m dying here. I know this is a standard part of Trump’s campaign-trail assurances, but, really, he thinks the editorial board is going to be impressed by a smart uncle?

Republican presidential front-runner Donald Trump visited the editorial board of The Washington Post on Mar. 21. Here is audio of the full, unedited interview. (Gillian Brockell/The Washington Post)

Trump’s point about his intellect, or at least the point he starts off with, is that he fully understands the “two phases,” campaigning and governing, and that presidential Trump will kick in once there is President Trump.

Candidate Trump had to knock off 16 opponents, he notes. “They are almost all gone. If I were going to do that in a different fashion, I think I probably wouldn’t be sitting here. You would be interviewing somebody else. But it is hard to act presidential when you are being — I mean, actually I think it is presidential because it is winning.”

Okay, one Trump, two Trumps, whatever. This is Forrest Gump meets Vince Lombardi. Presidential is as presidential does. Winning isn’t everything; it’s the only thing.

But back to Hiatt’s question: “Yet you are up there and talking about your hands and the size of . . . your private parts.”

The intention here is not to be provocative, or to get back into the gutter. It is to test, actually, whether Trump might be ready to enter a new, more mature phase. Marco Rubio — “Liddle Marco,” in Trump’s spelling — has said he regretted going there, and boy, should he. Does Trump wish he hadn’t responded in kind, hadn’t brought up the subject, unprovoked, at a presidential debate?

And here is the revealing part of Trump: He is not just a “counterpuncher,” as he tells us, he is a compulsive counterpuncher. Not only can he not refrain in the moment — he also cannot see another alternative in the cooling bath of hindsight.

“I had to do it,” he says, of responding to Rubio. “So, he started it.” Supporters were talking, Trump says, worrying about deformities. “I did this because everybody was saying to me, ‘Oh, your hands are very nice. They are normal.’ ”

Marcus: “You chose to raise it . . .”

Trump: “No, I chose to respond.”

Marcus: “You chose to respond.”

Trump: “I had no choice.”

Marcus: “You chose to raise it during a debate. Can you explain why you had no choice?”

Trump: “I don’t want people to go around thinking that I have a problem.”

This went on until Hiatt, sounding somewhat exasperated, most likely with me, cut it off: “Okay, let’s move on here. Let’s move on.”

If only.

You could argue that we should have drilled down more. One topic we didn’t manage to get in: How Trump would balance the tension inherent in his lament about the size of the debt, the sorry state of America’s infrastructure — and the proposal for a $10 trillion tax cut.

You’d be right, of course. Trump is the master of deflection, and the media’s concentration on the Trump outrage du jour serves to protect him from searching inquiry.

We tried to remedy that. But the hands discussion was illuminating, because presidential character is as important as presidential intellect and preparation. Being presidential doesn’t only mean winning. It also means being in control of your responses, being measured in how you deal with opponents, foreign and domestic.

Trump’s personality — you don’t have to deduce this; he has told us — is such that he cannot allow an insult to go unrebutted. In a potential president, this trait is as scary as any of Trump’s substantive flaws.

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