President Obama and his aides haven’t completed their policy review for Afghanistan - one of the most dangerous of the many foreign policy disasters George W.Bush so blithely left behind. But the situation is unraveling so quickly that aides say that the president decided that he had no choice but to send another 17,000 troops while commanders and diplomats try to come up with a strategy to stop the bloodletting and to try to block the Taliban from recapturing the country. There isn’t a lot of time.

In coming weeks, Mr.Obama will have to grapple with a series of very difficult questions starting with how he will define success in Afghanistan. The president will have to consider whether to keep supporting a central government in Kabul or focus more on cultivating local leaders. The rampant corruption of President Hamid Karzai’s government has driven far too many Afghans back to the extremists.

During the campaign, Mr.Obama said that he was open to talks with some Afghan militants. In recent weeks, American commanders said they are expanding contacts with so-called moderate members of the Taliban. At this point, there may be no other choice.

But we are deeply skeptical that there is any deal to be cut with Taliban leaders who gave sanctuary to Al Qaeda before 9/11 and would undoubtedly insist on reimposing their repressive, medieval ways, including denying education and medical care to women.

Mr.Obama and his team also must quickly come up with a plan to more effectively expand and train the Afghan Army (which eventually must replace American and NATO troops) and police force, curb a $720 million Afghan opium industry that finances the Taliban and encourage development along the Afghan-Pakistan border.

Mr. Obama will have to figure out a way to persuade NATO allies to send more troops - with orders to fight - and more money. Along with the United States, Britain, Canada and the Netherlands have been carrying nearly all of the burden. The new American president has rock star ratings in Europe. He needs to leverage some of that to get leaders there to finally contribute.

Mr.Obama’s biggest challenge will be trying to figure out how to persuade Pakistan that the fight against extremism is not a favor to the Americans. It is essential to Pakistan’s own survival.

The nuclear-armed country faces terrifying problems: political and economic instability, home-grown extremists who are far too cozy with Pakistan’s intelligence services, a lawless border region used by the Taliban to execute bloody attacks on Afghanistan. The government has effectively ceded the Swat Valley - which is in the border region but just 160 kilometers from Islamabad - to militants in a misguided bid for a false peace.

The White House’s decision to bring senior Pakistani and Afghan officials into the policy discussion is very welcome. Saudi Arabia, Iran and India must also be involved.

Mr.Obama goes to Europe the first week of April for a NATO summit. He has told aides to come up with a strategy for Afghanistan and Pakistan before then. Given how fast things are coming apart in Afghanistan - the Taliban have now moved into peaceful areas near Kabul - they may have to decide even faster.