Over the past four months Mahmoud Abbas has dug himself into a very deep hole in the Palestinian West Bank. Next month, he will try to blast himself out with what he hopes will be a controlled explosion — mass demonstrations by Palestinians that, he supposes, will neither turn against his regime nor get out of hand.

Abbas’s desperate gambit may turn out to be a dud. It might be called off at the last minute. But it also may be the trigger for another violent upheaval in the Arab Middle East — and one that changes the course of the poorly named “Arab Spring.”

First, let’s describe the hole. Back in April, frustrated with the Obama administration’s failure to deliver the concessions it had sought from Israel, the 76-year-old Abbas decided to pursue an entirely different strategy. He would arrange a reconciliation with the Gaza-based Hamas movement, then seek recognition of a Palestinian state at the United Nations.

In the following weeks it slowly became clear that Abbas and his aides had failed to think through their idea. U.N. statehood recognition can be blocked by the United States. A vote by the General Assembly for recognition as a “nonmember state” would pass but might draw damaging negative votes from Washington and much of Europe. Either the U.N. initiative or the formation of a joint government with Hamas would probably prompt Congress to cut off U.S. aid, which amounted to $500 million this year. That will trigger an instant economic crisis in a West Bank that has been enjoying a rare burst of prosperity.

Worst of all, the grand statehood initiative is likely to produce nothing tangible for average Palestinians, other than the loss of their jobs. There will be no Israeli withdrawal, no stop even to the expansion of West Bank Jewish settlements. No wonder that resistance to the Abbas plan has been steadily growing: Not just the Obama administration but the Jordanian government, Hamas and Abbas’s own prime minister have made it clear that they regard his initiative as foolhardy.

Hence, Abbas’s appeal, first delivered in Ramallah late last month, for “mass action, organized and coordinated in every place,” to accompany the U.N. vote. The idea is to stage huge, Arab Spring-style rallies in Ramallah and other West Bank towns beginning in early September, building to a climax when Abbas addresses the General Assembly on Sept. 21.

In theory, this will move countries to vote for Palestinian statehood, make Israel look isolated, attract the attention of Arab satellite channels and create at least the illusion of a triumph when Third World votes push the meaningless General Assembly resolution over the top.

The alternative is the exposure of Abbas’s fecklessness. “Abbas’s problem is that he will be humiliated if the U.N. votes and then nothing happens on the ground,” says a senior Israeli official who is deeply involved in planning for September. “So he is planning to jump on the back of a tiger. The problem is that if he loses control of the tiger, he is doomed.”

The Palestinians say they have a plan for that. The rallies will be carefully policed; they will be restricted to West Bank towns, far away from Israeli soldiers and settlers. Officials around Abbas say they recognize that if the demonstrations turn into a “third intifada,” they will be the losers: They will be swept from power by a more militant group of leaders.

Israelis, too, know they have much at stake. “Ten bodies could change the Middle East,” said the senior Israeli official I spoke to, who also said that Israeli army and police officials are engaged in intensive preparations aimed at avoiding violent clashes.

It’s not hard to imagine what could go wrong in a “third intifada.” The embattled dictatorships of Bashar al-Assad in Syria and Moammar Gaddafi in Libya could get a saving break as Arab attention focused on a new Israeli-Palestinian fight. Syria and Iran could promote new marches on Israel’s borders from the Golan Heights and Lebanon. Extremists in Egypt could use anger against Israel to whip up support in crucial elections scheduled for November. And so on.

The Obama administration, European governments and Israel’s right-wing government have been trying to come up with a diplomatic initiative that would give Abbas a reason to call off his plan: For example, a U.N. Security Council resolution that would lay out terms for Palestinian statehood and urge that negotiations resume. But the effort has been underpowered and for now seems unlikely to succeed — though some September brinkmanship can be expected.

If something stops Abbas, it will probably be Palestinians themselves. A recent poll showed that two-thirds of them oppose a third intifada, and only 14 percent said they would participate in one. If the world is lucky, the plan for a September explosion will turn out to be just another Palestinian dud.