[UPDATE From Americans for Peace Now: “With peace efforts stalled, the entire world is wondering if Senator Mitchell’s departure discloses a decision by the Obama Administration to back off further from peace efforts. It is vital that President Obama demonstrate – through his actions and words – that this is not the case. Now is the time for President Obama to take charge personally of his Israeli-Palestinian policy.  Envoys and shuttle diplomacy have had their day; what is needed now is resolute personal engagement and dramatic action from the President himself.”]

Next week, it seems President Obama will deliver a major speech on the Middle East, in an effort to portray the momentum shifting in the region from Osama bin Laden to the “Arab spring.” He’ll also meet with visiting Prime Minister Netanyahu of Israel and with Jordan’s King Abdullah. But he’ll do all of it without George Mitchell, who’s quitting.

Back in January, 2009, the appointment of former Senator Mitchell of Maine as Obama’s Middle East envoy won much applause from people who thought Mitchell was the right man to steer American policy away from overweening support for Israel to “even-handedness.” At AIPAC and elsewhere, Mitchell’s appointment sparked consternation and worry. But two years of bungling and ineptitude by the Obama administration—and its placid refusal to get tough with Israel or to demand that Netanyahu approach peace talks with an offer on the table—has led nowhere. Whether or not Mitchell had simply had enough, or that his resignation was truly for “personal reasons,” isn’t yet clear.

But it puts even more onus on Obama to finally, once and for all, declare his intentions on Middle East policy by putting forward an American peace plan. Everyone knows what it would entail: Israel must retreat to the 1967 borders, accept a Palestinian state with small adjustments to those borders, divide Jerusalem, and work out an acceptable deal over the Palestinians’ right to return to their homes in Israel. (In practice, that means a token return and generous financial compensation for Palestinian refugees.) The United States might also sweeten the pot with security guarantees for Israel. And Israel will have to remove most, if not all, of its illegal West Bank settlements.

In any case, Mitchell had pretty much given up. “Mitchell hasn’t been in the region in three months,” said a senior adviser to Palestinian President Abbas. “Whether he resigns or not, it’s clear that Mitchell wasn’t in the region because he didn’t see the possibility of being a mediator between two sides where one of them is not responsive.”