So what now? Barack Obama began his presidency with a broad strategy for the Middle East that included some kind of outreach to Iran, offering real inclusion into the international system in exchange for verifiable abandonment of nuclear weapons and cessation of terror sponsorship. The strategy was classic Obama: he laid out the terms clearly in advance and waited for his interlocutor to respond. The Cairo speech this month was the culmination of the charm offensive — a direct appeal to the people of Iran to turn their country around to a more responsible and peaceful path.

Obama’s problem is that it worked a little too well. The millennial generation that elected Obama in America also exists in Iran, in proportionally even greater numbers. They live and breathe on the web — especially in Iran, where free association in public is so fraught with risk of repression. They didn’t give Mir Hossein Mousavi his victory, just as they didn’t give Obama his landslide. But they did galvanise a long-suppressed yearning for a saner foreign policy, greater social freedom and a more than minimal grasp of market economics. And so the green wave built — slowly at first and then, in the final weeks of the campaign, like a tsunami.

Tehran’s elites, like Washington’s last year, did not see this coming. But Dick Cheney, George W Bush’s vice-president, did not respond to Obama’s victory by declaring that John McCain had won Illinois in a landslide. And so we entered the thrilling, horrifying, chastening period of the past two weeks.

What now? It depends, of course, on what emerges in Iran in the near future. But if Ayatollah Khamenei and President Mahmoud Ahmadinejad and the architects of the coup prevail, Obama would be hard pressed to abandon his realist task of engaging the regime. Talking to Tehran directly is a cornerstone of Obama’s foreign policy. And yet engaging the regime, even while the dictators still have on their hands the blood of Neda Soltan, the woman protester shot dead in Tehran, risks offending the very generation he inspired in Cairo and before. If Khamenei has just painted himself into a tight corner, he has also pushed Obama into one, too.

For Obama has his domestic crosscurrents as well. The neocon right, spearheaded by McCain, was already having kittens because Obama did not respond to the unrest by climbing on a pedestal and pulling a Bush. Many are already gunning for Obama for daring to demand that Israel cease expanding settlements on the West Bank. They are trying to push the idea that Obama is another weakling Jimmy Carter, even though it is hard to see Carter coolly ordering his snipers to shoot three Somali pirates in the head. Or rather it is hard to see Carter ordering his snipers to shoot three Somali pirates in the head — and succeeding.

Obama, in fact, is much more like Eisenhower or the first President Bush than he is like Carter. He earned praise from Brent Scowcroft and Henry Kissinger, the former national security advisers, for his handling of Iran. A mix of cerebral and steely, Obama has put Stanley McChrystal, one of the most hardcore special ops commanders, in charge of Afghanistan and is handling Iran’s crisis less like Carter and Soviet Russia in 1979 than Bush and Soviet Russia in 1990. But that risks alienating the bleeding-heart liberals in his base, who understandably flinch when seeing a Democrat get all pragmatic with murderous theocratic nut-jobs such as Ahmadinejad.

What now? That will depend on what transpires in Iran, how the regime responds to the collapse in its legitimacy, how its internal factions jostle and who ends up pulling the biggest strings. One school of thought among the Obamaites is that this episode could have so weakened Khamenei that he may be eager to make a deal with Obama to win back some support from the Mousavi voters. That might help in Afghanistan and Iraq, but not on the nuclear programme — which Mousavi backs as well.

Another, more realistic, school believes that Khamenei will harden his stance against the West even more, because he needs to shore up his base, and will construct a new external enemy to justify further repression. The problem here is that he no longer has Bush to demonise.

Yet another thinks this is a great time to play Syria against Iran and to use the common antipathy to Iran among Sunni Arab regimes and Israel to broker an Israeli-Palestinian settlement. And that, in turn, could undermine the anti-Zionist claptrap that operates as a kind of rhetorical Viagra for the ageing Khamenei cabal. Well, it’s a plan, I suppose. I wouldn’t get my hopes up.

The key to Obama’s approach, I suspect, is his respect for Reinhold Niebuhr, the great theologian and political theorist who appreciated the power of non-violence and community organisation — he was of the Gandhi and Martin Luther King generation. But Niebuhr also understood the necessity of using force and playing hardball in foreign relations in a fallen world. This “Christian realism” has rarely been as relevant as it is today — and it’s deep in Obama.

A strategy of total disengagement from Iran, isolation and war might be morally and rhetorically satisfying, as it was for George W Bush, but it might be less morally responsible to the people of Iran and the peace of the world than an unsavoury attempt to grapple with an evil regime with open eyes. Balancing these two imperatives — of always being open to peace and dialogue while always being girded against appeasement — is what Niebuhr teaches we cannot and must not avoid. It will mean a vulnerability on Obama’s part to being called weak or contradictory; but it may also be the only way to secure a practical peace.

Think of it in game theory, as the British blogger Marbury did last week. Obama is playing “Retaliator”. He starts out as a dove and waits to see the response. If the response is also a dove, he reciprocates and builds trust for mutual benefit. If the response is a sharp-clawed hawk, he becomes a hawk. But the dove’s posture is always there beneath and is established early for maximal advantage. What Obama wants to do now is what he tried to do in Cairo — to lever the people of Iran against their rulers. He won’t take the bait of easy conflict, but neither will he concede without a Khamenei concession. So the pressure builds on the Tehran regime from within and without. And Obama carefully and methodically bides his time.

Bush was playing draughts; Obama is playing chess. And it’s Khamenei’s move.

www.andrewsullivan.com

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