I'd like to tell you who's going to be the next secretary of state. But I can't. It's a secret.

Still, I'm not the only one who knows. One very plugged-in friend of mine says that she's talked to Pete Rouse, the Obama advisor now assembling lists of names for President Barack Obama's second-term cabinet, and he says that Senator John Kerry has the short odds. But a White House correspondent responded by e-mail that, in fact, Kerry is "a long shot," since Obama won't want to risk losing a Senate seat, that U.N. Ambassador Susan Rice is still the leading candidate, but that national security advisor Tom Donilon "REALLY wants it." Then, the New York Times reports that Donilon doesn't want it, and that Rice is "crippled" because GOP senators will use the confirmation hearing to torture the administration over Benghazi. That's the problem with rumors: Knowledgeable people know things that contradict what other knowledgeable people know.

Since, to be honest, I don't know what Obama is thinking -- and neither does anybody else I've talked to -- let me try to answer instead the question of who it would make the most sense for him to appoint. I think the answer is pretty clearly John Kerry. Tom Donilon is a highly competent administrator who would die of impatience halfway through an interminable lunch with Afghan President Hamid Karzai. Susan Rice is a pugnacious team player who, like Donilon, is more insider than outsider, and is notably deficient in that unctuous fluid which issues from the pores of professional diplomats. She would make a very good national security advisor if Donilon goes elsewhere. Obama, by all accounts, trusts Rice's judgment and is very fond of her; but he may be penetrating enough to see her shortcomings.

John Kerry is Hillary Clinton in pants. (Yes, I know, Secretary Clinton also wears pants.) He came within a whisker of being president -- much closer than she did -- and thus enjoys the aura of the almost-commander in chief. He is, like Clinton, a kind of living embodiment of America. He is immensely solemn and judicious, like her, but, unlike her, immensely tall. He is a decorated veteran with the iron grip of the ex-athlete. His baritone voice bespeaks bottomless gravitas. The man looks and acts more like a secretary of state than anyone since George Marshall. As a casting decision, it's a no-brainer.

It's important to understand what space Kerry, or someone else, would be seeking to fill. With a few important exceptions, Hillary Clinton has not been asked to formulate America foreign policy but rather to represent it, to talk about it, and to execute it. And she has done so almost flawlessly. If she is a conceptual thinker, she has kept her vision to herself. The big thinking in this administration comes from the Big Thinker in the White House, and a very small circle of aides. That is unlikely to change. And Kerry, though deeply familiar with everything and everyone, poses no danger of trying to impose a worldview of his own. He is an implementer, not a thinker. Tell John Kerry to take that hill, and he will take that hill or die trying.

Then there's the foreign policy work that needs to be done. The Obama administration will spend the next few years trying to extricate itself from Afghanistan -- and, collaterally, Pakistan -- with the least possible risk to America's reputation or national security. Kerry has been the White House's designated placater of Hamid Karzai and Pakistan's military chief of staff, Gen. Ashfaq Kayani. He visited Pakistan in the aftermath of the arrest of CIA agent Raymond Davis, and the killing of Osama bin Laden; and both times he left cooler tempers in his wake (though the effect didn't last). In 2009, he listened to Hamid Karzai rant for hours about how the world was shafting him before finally persuading Karzai that it was not in his own interest to accept the outcome of the transparently rigged election which had just won him a second term as president. If anyone can talk those guys off a ledge, it's Kerry.

All presidents want to bring peace to the Middle East. They all fail, but that doesn't stop them from trying. Nor should they. In the first term, Obama delegated that task to George Mitchell, his special representative. That won't work; the Israelis need to feel that they are the most important thing in the world, just as the U.S. Congress tells them they are. John Kerry has known Israel's prime minister, Benjamin Netanyahu, since the latter was making a living in Cambridge, Massachussetts, some twenty-odd years ago. I have heard him say nice things about Netanyahu off the record. He knows everyone who matters in Israel, Saudi Arabia, Qatar, and Turkey. If a relationship of trust confers any advantage -- and I'm not convinced that it does -- Kerry has that edge.

Kerry is also a world-class listener. When I traveled to Afghanistan with him in 2010, he let me sit in while he met with a leading human rights campaigner. "Tell me where you think we are," he said. And, "What do you think are the chances of a civil war?" And, "What is the U.S. doing wrong?" And "What is your most important advice for us?" It has to be very flattering to be so earnestly interrogated by an enormously tall man who was almost president of the United States. Tom Donilon and Susan Rice can't do that. John Kerry will make heads of state everywhere feel that American policy is in good hands. He is the secretary of state they would choose if anyone was asking.

But this is a limitation, too. The world has been knocked from its moorings; some of the friendly autocrats Kerry had spent years cultivating, like Egypt's President Hosni Mubarak, have been toppled by popular outrage. Kerry's understanding of the world has been profoundly shaped by the countless hours he has spent talking to leaders in their palaces. He understands their problems. After repeated visits to Syria, for example, Kerry became convinced that President Bashar al-Assad was a man the United States could do business with. Assad and his wife drove Kerry to a mosque in Damascus and spoke sadly of the decline of secularism and the rise of Islamic fundamentalism. Kerry nodded his great, graven image of a head. He asked Assad to take confidence-building steps, and Assad came through. Good friends like the Emir of Qatar told Kerry that Syria held the key to Middle East peace (see this striking WikiLeaks cable). But the Arab autocrats club is history.

The point is not that Kerry is naïve, or soft on dictators. It's rather that he is, to a profound degree, a status quo figure who deals with the world as he finds it. When I taxed him over his role in Syria, he said to me, "Countries and people and leaders of countries act out of self-interest. Foreign policy is the art of finding those interests and seeing what serves your nation and trying to marry them." Kerry operates one small turn of the wheel at a time. But his caution goes further than that: He also accepts the existing terms of debate. Throughout the 2009 debate on policy towards Afghanistan, when Vice President Joe Biden was torturing the generals with tough questions about counterinsurgency and proposing a sharply different alternative, Kerry was keeping mum. He has never deviated sharply from the administration position on this or almost anything else. Kerry is prepared to pilot the boat in the face of incoming fire, but not to rock it. He has courage -- but not intellectual courage.

Perhaps Kerry would be more outspoken inside the White House than out. He is not one to speak out of turn. The combination of his natural ponderousness and his extreme care about secret discussions often make him maddeningly vague in public. His default public posture is a kind of high-minded WASP propriety. In private, he is a gracious man with impeccable manners, genuinely curious about others, at times touchingly deferential.  And the same restraint and reserve which made him such an unsatisfying presidential candidate have also made him the kind of consummate diplomat whom the White House has counted on to soothe troubled waters in Afghanistan, Pakistan, Sudan, and elsewhere.

Kerry has shortcomings. Who doesn't? But I can't think of anyone who would be better for the job.