IT’S THE GRANDDADDY OF ALL American diplomatic achievements in the Middle East. It represents one of the greatest Western victories of the Cold War. It has prevented the drift toward a region-wide Arab-Israeli military confrontation for more than 30 years. It is the foundation both of Israel’s security doctrine and the Jewish state’s transformation from an economic basket case into a firstworld economic power. It has made possible every hopeful move toward Arab-Israeli peace for the past generation. And it – the Egypt-Israel peace treaty – is hanging on by a thread.If the audacity of the joint Palestinian- Egyptian, Gaza-to-Eilat terrorist attack in mid-August were not scary enough, its potential to explode into a full-blown Egypt- Israel crisis was positively frightening.In an instant, the real news story – a joint Palestinian-Egyptian team of jihadist terrorists march 200 kilometers across Sinai and then cross the border to launch multiple attacks on civilian targets, only to return to Egyptian territory and escape into the biblical wilderness – was airbrushed from history and the airwaves were instead filled with Arab condemnations of Israeli perfidy for having the temerity of trying to pursue, kill or capture terrorists.Throngs took to the streets denouncing the Camp David agreements and politicians took turns ramping up the popular frenzy by calling for the recall of the Egyptian ambassador, the expulsion of his Israeli counterpart, and even the suspension of the peace treaty itself.Cooler heads eventually prevailed.Lubricated by an almost-apology from Israel’s defense minister and a private visit by a senior Israeli defense official, Egyptian officialdom – in the person of Minister of Defense and de facto head of state, Field Marshal Muhammad Hussein al-Tantawi – finally decided to calm the situation.The lameduck Egyptian foreign minister helpfully reminded his countrymen that Egypt’s national interests are well-served by having an ambassador in Tel Aviv and the Supreme Command of the Armed Forces, the country’s ruling clique since the ouster of Hosni Mubarak, launched an operation to reclaim a measure of control in the largely lawless Sinai. Perhaps reflecting the military’s mood, a proclaimed “million-man march” against Israel drew only a few hundred protesters.Still, the damage was done – or to be accurate, the aftermath of the Sinai attack only confirmed how firmly embedded in Egyptian political culture is the phenomenon of antipathy toward Israel. Today, there is no major political figure left on Egypt’s national scene willing to defend peace with Israel. Among the Islamists, whose poisonous anti-Semitism has been diluted of late as a tactic to earn swooning praise from international media and global democracy activists, this is no surprise.But this is even the case among the alleged liberals. Both Ayman Nour, the Ghad party leader who owes his freedom from Mubarak’s jail to the importuning of American political leaders and activists (many of them Jewish) and Amr Moussa, the populist former Arab League secretary general who earned a reputation among diplomats as a practical-minded wheelerdealer when he served as foreign minister, have declared the Camp David era over. And they may be the best of the lot.TO BE ACCURATE, WHILE Egyptians evince no zest for peace with Israel, they also show no appetite for war. Militias aren’t forming to liberate Palestine; the same Muslim Brotherhood that sent activists to help prevent the nakba during the Israel War of Independence 63 years ago is far more concerned today with balancing three competing domestic goals – achieving electoral success, preventing being outflanked by the even more radical Salafists, and managing its on-again/off-again partnership with the country’s military leadership.Egyptians, the saying goes, are committed to the Palestinian cause, just not to the Palestinian people. The result is that many believe they can exist in a nether state of no war, no peace.After years of reducing the relationship with Israel to its most minimalist components, it is not difficult to see how many Egyptians could reach that conclusion. On the eve of the Tahrir Square uprising, the entire relationship between these two neighbors had been whittled down to the sale of gas, the operation of several low-profile economic zones, measured security cooperation in constraining the activities of radical jihadists (especially those targeting Egypt) and an uneasy political ménage à trois with the United States.Israeli leaders visiting Cairo made a beeline to the presidential palace for tea with Mubarak, a conversation with his intelligence chief and perhaps his minister of defense, and flew home, satisfied that they had checked the Egyptian box.For years, this was sufficient – until it wasn’t anymore. In the absence of public political investment – which Egypt’s leaders never wanted to make and Israel’s leaders never considered essential – none of these factors are strong enough, individually or collectively, to sustain a long-term relationship.Indeed, little of this is even likely to survive Egypt’s revolutionary fervor.Still, there is a huge difference between an Egypt at peace with Israel, locked into a series of contractual obligations, sustaining at least the skeleton of a security and intelligence relationship, and desirous of Israeli-Palestinian diplomatic progress, if only to validate its original go-it-alone move, and an Egypt untethered by any formal relationship with Israel, swaying this way and that with the gyrations of the public mood, sliding (perhaps backsliding) inexorably from peace to non-belligerency, to even worse.Forget the Palestinian gambit at the United Nations. Don’t lose sleep about Grad missiles from Hamas. Fear not the threats of Syria’s Assad, Hizballah’s Nasrallah or al- Qaeda’s Zawahiri. Compared to the potential demise of Egypt-Israel peace, a huge bonanza to radicals of every stripe and a strategic calamity nearly on par with the acquisition of nuclear weapons by the Iranian mullahs, these are mere annoyances.Ultimately, preserving Egypt-Israel peace, at least to prevent a slow (and perhaps not so slow) descent into belligerency, will be a team effort. Everyone with an interest in its preservation has a role to play.For the Egyptian military, that means prosecuting “Operation Eagle” – the effort to recapture control of the Sinai – to the fullest, sending the entire complement of 2,000 allowed troops into the peninsula (not just 750) and rejecting the idea of an uneasy truce with the Islamist-Bedouin alliance that owns much of that empty space. On the political level, this will also see the military playing the pre-Erdogan role of the Turkish army in terms of preventing Egypt’s rambunctious, revolutionary political discourse from straying into areas where it risks national security.For Israel, this will require the unnatural act of diplomatic subtlety, creativity and restraint. For example, whereas Israel has legitimate grounds not to apologize to Ankara over its outrageous role in the “Mavi Marmara” incident, the Egyptian government’s actions in the Sinai attack were nothing like that of Turkey’s at sea; a more generous statement on the unfortunate killing of Egyptian security forces might have been both appropriate and helpful.Other Arab states should act, too. Saudi Arabia may be no lover of Zion but the Saudis have no interest in a hostile Egyptian- Israeli relationship diverting attention from the Iranian quest for regional influence.Here, Riyadh can help by stopping the flow of money to Salafis and other radicals that has the impact of distorting politics and accentuating the extremist narrative.Ultimately, this effort will not succeed without Washington. History will not be kind to President Barack Obama if he decides he can trade a minor success in Libya for a strategic catastrophe in Egypt. America’s influence in the Middle East depends on its relationships with Israel, Egypt and Saudi Arabia. With Israel and Saudi Arabia, the relationship is bound up in other equities (with the former, historic, popular, cultural and strategic bonds; with the latter, oil).With Egypt, the link is Camp David. If that connection suffers, America’s standing in the region suffers, too. This will require high-level U.S. engagement, both before and after Egypt’s election season, to remind Egyptians what is at stake in their choice of political leaders and to remind those leaders that their choices have consequences.In the end, two decades of disuse and neglect may have made salvaging Egypt- Israel peace in the post-Mubarak era an impossible task. But the stakes are too high not to try. • Robert Satloff is executive director of The Washington Institute.