This will help in multiple ways: First, this guarantee of a long-term U.S. commitment to Afghanistan will encourage other NATO countries to maintain some of their own troops in Afghanistan to work with the Afghans in areas like training the army and police past the end of the NATO combat mission in December 2014.

Such an announcement will also help reassure Afghans that the United States won't be simply turning off the lights in Afghanistan in December 2014. And it will signal to regional powers like Pakistan and Iran that the United States plans to remain engaged in Afghanistan for many years into the future.

A key issue facing the Afghan government as the United States draws down its forces is how will the Afghan economy fare? Should the economy collapse, the Afghan government's ability to deal with security issues would be substantially eroded. Already, rents in Kabul are tumbling and nongovernmental organizations are laying off staff.

Surprisingly, however, a rigorous and comprehensive World Bank study last year found that Afghanistan will continue to have a healthy growth rate, dropping from its present robust 9% a year rate "to closer to 5% on average until 2018." (The U.S. economy's yearly growth rates over the past four years have been around 2%.)

The economic contraction as the United States draws down is likely to be less severe than might be supposed, partly because the hundreds of billions that the U.S. military has spent in Afghanistan over the past decade is spending that almost entirely benefits the United States.

The World Bank study points out that "military spending by the United States (and other countries) finances the salaries of military personnel, investments in weapons equipment and systems. ... The impact of its withdrawal is therefore likely to be muted."

Another encouraging sign is the investigation of the troubled Kabul Bank, in which some $900 million was lost to fraud, indicating that the culture of impunity for corrupt Afghan officials might be beginning to erode. Earlier this month, 21 officials were found guilty of fraud and two of the former heads of the bank were sentenced to five years in prison. The Afghan Attorney General's office said last week that it would appeal the sentences as being too soft given the scale of the fraud.

A key question is the extent to which the Afghan army and police can operate effectively against the Taliban as the United States withdraws. As yet the Afghan army hasn't shown the ability to conduct large-scale operations without significant American support. In addition, a big issue for the army is the extraordinarily high attrition rate.

Today, a little more then a quarter of the recruits to the army drop out every year. Because of this high dropout rate, NATO is now considering maintaining the Afghan army and police at its present large size of 352,000 men through 2018. (Estimates of the size of the Taliban typically are in the 25,000 range.)

One indicator of the increasingly Afghan-led nature of the fight against the Taliban is the fact that some 300 Afghan soldiers and policemen are now dying every month in the war, while in January three U.S. soldiers were killed, which was the lowest number of any month during the previous four years.

On Afghanistan, Pakistan has some important common goals with the United States, NATO and Afghans themselves. Pakistan does not want to see Afghanistan collapse into a renewed civil war, which would destabilize Pakistan, nor does it want to see the Taliban in charge of the country again.

When the Taliban was in power in Afghanistan the group resisted Pakistani efforts at control, while the Pakistani Taliban have killed many thousands inside Pakistan. These basic shared goals, no civil war and no Taliban control of Afghanistan, can help to create the conditions for a successful post-2014 Afghanistan

Pakistan also wants a Pashtun-led government in Kabul and for the Taliban to have some representation in the south and the east. These are also goals the Afghans can live with.

Karzai is, after all, a Pashtun and given the fact that Pashtuns are the largest ethnic group, the next president of Afghanistan almost certainly will be a Pashtun. And other ethnic minorities can live with a situation in which the Taliban assume a number of provincial and district governorships providing they lay down their arms, join the political process and recognize the Afghan constitution.

According to a senior Afghan government official, numerous discussions between representatives of the Taliban and the Afghan government have taken place over the past years to discuss such a political accommodation, although, so far, not much of anything has come of these talks.

Note: This story is adapted from testimony by Peter Bergen delivered to the House Foreign Affairs Committee on March 19, 2013.

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