Watching Tuesday's three-way meeting in New York between President Obama, Israeli Prime Minister Benjamin Netanyahu and Palestinian Authority President Mahmoud Abbas -- and the administration's effort to spin it into a success -- reminded me that when breakthroughs in Arab-Israeli peacemaking come, they come with unforeseen and unpredictable urgency driven by big men and big events.

Today we have neither, just the prospects of a long, hard slog -- a thousand days of root canals created for the would-be mediator by Israeli and Palestinian leaders who are prisoners, rather than masters, of their political worlds, and by gaps on the core issues, such as Jerusalem, that are galactic in scale. In the middle sits a potentially transformative American president who somehow hopes to compensate for their absence of leadership with his own strength and vision.

Having spent the better part of a quarter of a century as a negotiator working on the Arab-Israeli conflict, I know how easy it is for longtime observers to get cynical about the prospects for peace. But that's unfair; after all, the wheel turns, and with it comes a new administration, new circumstances and new ideas that can sometimes lead to movement in an all-too-often stagnant process. Still, when William Faulkner wrote that "the past is never dead; it's not even past," he cautioned all of us to respect history's power.

And history, when it comes to the Arabs and Israelis, is worth pondering. It teaches that only when the regional table is set with the realities of pain and gain can America, pursuing relentless and reassuring diplomacy, forge agreements between the two sides.

It was the 1973 war, for instance, that allowed Henry Kissinger to use crisis, pressure and incentives to broker three disengagement agreements in 18 months; it was Jimmy Carter, rescued by Egyptian President Anwar Sadat's extraordinary trip to Jerusalem in 1977, who brokered an Egyptian-Israeli peace treaty. And it was Iraq's August 1990 invasion of Kuwait that triggered Operation Desert Storm and opened the way for James Baker's tough and smart diplomacy that compelled three strong but recalcitrant leaders (Yitzhak Shamir, Hafez Assad and Yasser Arafat) to send their negotiating teams to Madrid in October 1991.

The challenge, of course, for the Obama administration is that it lacks the stuff of which Arab-Israeli breakthroughs are made, particularly the leaders who must make the tough decisions.

On the West Bank, a Palestinian Humpty Dumpty offers itself up as a prospective peace partner for Israel. Abbas and Prime Minister Salam Fayyad are good, reasonable men who know that history compels them to do pragmatic diplomacy. But although they have the incentive to make peace with Israel, they do not have the power. Hamas, on the other hand, has a different understanding of history's long arc. Consequently, it has the power but not the incentive to settle with Israel. Empowering Abbas makes sense on paper, but it is beyond the capacity of this Israeli government or even the United States. To do so would require Israel to adopt a real freeze on settlements and to take positions in negotiations that meet Palestinian national aspirations, including parting with half of Jerusalem as a Palestinian capital.

And even if the Israelis were to promise all this, they might well be making concessions to a Palestinian partner who lacked a monopoly over the legitimate forces of violence in Palestinian society and didn't control all of the guns. Can any Palestinian leader really recognize Israel and accept it as a state of the Jews and also provide the security guarantees to allay its existential concerns? Israel's fears run deep. "We fight the Arabs during the day and win," goes an Israeli saying, "and fight the Nazis at night and lose."

In Israel, meanwhile, a different battle rages within a deeply divided and rudderless society. Israel is burdened by history and shackled by a settlement enterprise it may not be able to escape; it is uncertain still about what price it is prepared to pay on Jerusalem, territory and refugees to end its conflict with the Palestinians.

The prime minister himself is a reflection of this terrible ambivalence. The part of him that is a tough, suspicious Likud Party pol wrestles with the part of him that aspires to greatness and to lead Israel out of the shadow of the Iranian bomb to a lasting peace with the Arabs. Which will win -- the surviving politician or the risk-ready statesman? Even he doesn't know. They say an Israeli prime minister sleeps with one eye open; this one is sleeping with two eyes open wide.

It's against this grim backdrop that Obama, the transformer, seeks to leave his mark. Smart and savvy, he knows that governing is about choosing, about setting priorities. Given all the other battles he's waging at the same time, the smart money is on his taking the easy road, the small deal, managing the Arab-Israeli issue, maybe nudging into being a Palestinian state with provisional borders.

But who knows? Maybe the president will conclude that it's worth taking a crack at breaking the Arab-Israeli impasse; maybe an American vision is in store on borders, Jerusalem, security and refugees, and a package of security guarantees and real normalization with the Arabs to make it worth Israel's while. Indeed, perhaps the president sees that the kind of good fortune that smiled on Kissinger, Carter and Baker won't rescue America this time around, and that if he hopes to achieve what now seems unimaginable -- a conflict-ending Israeli-Palestinian solution -- he'll have to make his own breaks through tough, fair and reassuring diplomacy.