If President Obama has any strategy for a decent exit from Afghanistan, he is certainly keeping it a secret.

The latest White House effort to jump-start peace talks with the Taliban in Doha, Qatar, ended in an embarrassing fiasco. Then, last week, the White House once again floated the idea that it would pursue a “zero option” in Afghanistan, meaning Washington would leave no residual force behind after U.S. troops exit in 2014.

If this is the new U.S. exit strategy, it is destined to fail.

Some say floating the “zero option” is only a tactic to pressure Afghan President Hamid Karzai to be more cooperative with Washington. Others say the leak reflects Obama’s deep desire to wash his hands of the whole Afghan mess, and therefore could actually become American policy.

I asked Ryan Crocker, one of America’s premier diplomats and a former ambassador to Afghanistan, what he thought, and his anger was palpable as he responded: “If it’s a tactic, it is mindless; if it is a strategy, it is criminal.

“Nothing could encourage the Taliban more. The Pakistanis (who are helping the Taliban) will dig in harder. It will send Karzai in completely the wrong direction.

“It invokes memories of the early 1990s,” Crocker added, referring to the time when the United States abandoned Afghanistan after the Soviet withdrawal, leaving behind a failed state that became a haven for terrorists. “It’s as if we’re telling the Afghans, ‘We’re tired, we’re going home, screw you.'”

I agree with Crocker. Yet it’s clear that Americans are fed up with the long and costly war in Afghanistan. Obama hasn’t made the case for a continued troop presence and probably believes there would be little political or strategic cost to a zero option.

If so, he is wrong.

The importance of a residual military presence (of about 10,000 troops) is more about symbols than numbers. The main function of the troops would be to train and advise Afghans, but they would also symbolize a long-term U.S. commitment to the country’s stability.

Toward that end, the United States signed a bilateral strategic partnership accord with Kabul last year, negotiated by Crocker. A zero option would undercut that accord and signal that Washington is ready to abandon its commitments. It would weaken congressional and international pledges to fund Afghan forces and economic development over the next decade.

Perhaps this doesn’t matter, you might say. Why should we be helping a corrupt Afghan government that feeds on Western aid? Answer: If that government collapses, the country will plunge into civil war, with all of Afghanistan’s neighbors backing their proxies. Pakistan will support the Taliban, while Iran, Russia, and India will back other factions.

Afghanistan would once again become a failed state and potential terrorist haven, as it did in the 1990s. “We have seen this movie before,” said Crocker.

Only this time, the movie would have dangerous new actors and far grimmer pyrotechnics than it did two decades ago. The blowback from terrorists within Afghanistan would threaten a highly unstable and nuclear-armed Pakistan next door. And Washington would no longer have Afghan bases from which to carry out its favored antiterrorism policy: dispatching drones.

Administration officials insist that the president is still undecided about the zero option. Testifying before the Senate Foreign Relations Committee last week, James Dobbins, the administration’s special representative for Afghanistan and Pakistan, said Obama “is still reviewing a range of options” and “has not made a decision about the size of a U.S. military presence after 2014.”

But as the old saying goes, not to decide is to decide. Afghans are already making their decisions based on the belief that Obama wants a zero option. “The lack of clarity on this point has led to too much hedging in the region,” said Sen. Robert Menendez, D., N.J., the chairman of the Foreign Relations Committee. “Afghans who may otherwise be interested in building a fledgling democracy want to know that they will not be abandoned by the United States, as the Taliban claims they will be.”

Afghans smell betrayal in the air. U.S. officials insist they won’t negotiate a deal with the Taliban behind the back of the Afghan government. Yet, at the Doha talks, the Taliban acted as if it were the real Afghan government, insisting it wouldn’t talk with the American “puppet” Karzai. Then came the hints of a “zero option.” No wonder Karzai is furious.

In 1971, Henry Kissinger famously scribbled the phrase “We need a decent interval” in the margin of a briefing book that dealt with the withdrawal of American forces from South Vietnam. The phrase referred to his efforts to ensure there would be sufficient time between a U.S. troop exit and a likely communist takeover in Saigon — so that the Nixon administration wouldn’t be blamed for the defeat. That “decent interval” spanned two years, between the 1973 Paris peace talks with Hanoi and the 1975 fall of Saigon.

Unless Obama commits to, and leads, a more coherent diplomatic strategy — with talks that involve all the regional players, not just Washington and the Taliban — there may be no “decent interval” before Afghanistan collapses. It could happen before the end of his second term.