September 1, 2010: President Obama hosts the leaders of Israel, Jordan, Egypt and the Palestinian Authority in what is optimistically billed as the opening meeting of a year-long effort to finally arrive at a two-state solution for Mideast peace. Eight months later: Egypt’s Hosni Mubarak is deposed, King Abdullah of Jordan is clutching onto power, and the three remaining leaders are veering dangerously into uncharted and conflicting diplomatic territory. Only one of them can recapture the initiative — the host of last September’s meeting.

President Obama must articulate the outlines of an Israeli-Palestinian peace agreement based on America’s previously stated values and parameters. And he must do it soon, before Israeli Prime Minister Benjamin Netanyahu addresses Congress in late May, and before Palestinian President Mahmoud Abbas seeks a unilateral declaration of statehood at the United Nations in September.

Obama must take this risk — and, granted, it is an enormous risk — because it appears to be the only way to break the current stalemate and avert what Israel’s defense minister predicts will be a “diplomatic tsunami” if the U.N. acts as expected on Palestinian statehood. There is always a chance that Netanyahu will stun the world with a comprehensive, bold peace plan of his own, but sadly there is nothing in his tenure in office to warrant that hope, and every reason to believe that the Republicans who invited him to speak will continue to chase after questionable short-term partisan gains over Israel’s long-term survival.

The current stalemate has many authors. Netanyahu’s fealty to his right-wing coalition seems to have made him far more concerned about petty internal politics than the urgency of ending a 44-year occupation, the only way to maintain Israel as a Jewish and democratic state. Abbas squandered most of the 10-month partial settlement freeze that Netanyahu granted and now is banking on the U.N. to make an end run around the Israelis, which will only further alienate and isolate his peace partner.

Obama also played a role in this unfortunate drama. His administration has done more than any other to heighten Israel’s qualitative military edge in its tough geopolitical neighborhood, but his clumsy attempts to insist on a settlement freeze backfired, and he still hasn’t earned the trust of the Israeli public.

But that should not stop him now. The contours of a compromise are no mystery; President Bill Clinton outlined his “parameters” in December 2000, and they still make sense today. A sovereign Palestine that accomodates Israel’s security needs. Land swaps to allow a majority of settlers to remain part of Israel. Compensation for Palestinian refugees and opportunities for them to be resettled instead of an unfettered “right of return” to Israel. A shared Jerusalem, with Israeli and Palestinian authority over their respective neighborhoods and guarantees of protection for holy sites.

True, if Obama puts a peace plan on the table, he’ll immendiately become vulnerable to international pressure to follow up with American action and face domestic anger from some American supporters of Israel. He won’t be able to walk away. He will be gambling with nothing less than America’s prestige.

But what is the alternative? Maintaining a status quo that is unsustainable, especially now when the region is engulfed with democratic fervor? Allowing the Palestinians their diplomatic coup in September? Creating an opening for another government, one far less sympathetic to Israel, to play international mediator?

The scene from last September’s heady moment at the White House is now consigned to history. The message of 2011 is that leaders must deliver for their people. And when those leaders are unwilling to do what is necessary on their own, the United States has an obligation to strategically, forcefully show them the way.