Deciding what to do in Afghanistan requires a hard-nosed assessment of the costs of the war, the alleged benefits of victory and the likelihood of success.

We know the price will be high. The United States has spent more than $223 billion on the Afghan war since 2001, and it now costs roughly $65 billion annually. The actual bill will be significantly higher, however, as these figures omit the replacement cost of military equipment, veterans’ benefits and other war-related expenses. Most important, more than 850 US soldiers have already been killed and several thousand have been seriously wounded.

And we are not close to winning. The Obama administration admits that the challenges are “daunting,” and a recent pro-war report from the Center for American Progress said success will require “prolonged U.S. engagement using all elements of U.S. national power” for “as long as another ten years.” Success also requires creating an army and police force larger than the Afghan government can afford, which means Kabul will need US assistance indefinitely.

The bottom line: staying in Afghanistan will cost many more dead American soldiers–and, inevitably, Afghan civilians–and hundreds of billions of additional dollars.

But might the benefits be worth the costs? President Obama says we have to prevent Afghanistan from becoming “an even larger safe haven from which Al Qaeda would plot to kill more Americans.” But defeating the Taliban in Afghanistan isn’t the key to thwarting Al Qaeda. Indeed, even if our counterinsurgency and nation-building efforts exceed all expectations, the Afghan government will still have only limited authority over much of the country and will be unable to prevent Al Qaeda cells from relocating there.

Moreover, Al Qaeda doesn’t need lots of territory or elaborate bases to plot attacks and other conspiracies; all it needs are safe houses in various parts of the world and a supply of potential martyrs. Al Qaeda clones already exist in Yemen, Somalia and elsewhere; so denying its founders a “safe haven” in Afghanistan will not make that network less lethal. If Al Qaeda is our main concern, fighting in Afghanistan is increasingly a distraction.

Finally, America’s odds of winning this war are slim. The Karzai government is corrupt, incompetent and resistant to reform. The Taliban have sanctuaries in Pakistan and can hide among the local populace, making it possible for them simply to outlast us. Pakistan has backed the Afghan Taliban in the past and is not a reliable partner now. Our European allies are war-weary and looking for the exits. The more troops we send and the more we interfere in Afghan affairs, the more we look like foreign occupiers and the more resistance we will face. There is therefore little reason to expect a US victory.

Fortunately, pulling US troops out of Afghanistan will not make Al Qaeda stronger. If the Taliban regain power, they may conclude it is too risky to let Osama bin Laden return. But even if they did, a backward and landlocked country like Afghanistan is a poor location from which to attack the United States, which is why the 9/11 plot was conducted out of Hamburg, Germany. If Al Qaeda’s founders have to hide somewhere, better in Afghanistan than anywhere else.

And hide they will, because Afghanistan won’t be a safe haven. Bin Laden could operate somewhat freely there before 9/11, because the United States wasn’t going after him all-out. Those days are long gone. The Taliban will not be able to protect him from US commandos, cruise missiles and armed drones. He and his henchmen will always have to stay in hiding, which is why even an outright Taliban victory will not enhance their position very much.

In short, US victory in Afghanistan won’t put an end to Al Qaeda, and getting out won’t make it more dangerous. And if the outcome in Afghanistan has little effect on the threat Al Qaeda poses, there is little reason to squander more American blood and treasure there.

Obama’s decision should be easy, given that the costs of the war are rising, the benefits are few and the odds of success are small. If he explains that calculus to the American people and says it is time to leave, most of them will agree.

ALSO IN THIS FORUM

John Mueller

, “The ‘Safe Haven’ Myth”

Selig S. Harrison

, “The Ethnic Split”

Priya Satia

, “Attack of the Drones”

Manan Ahmed

, “Paranoia Over Pakistan”

Mosharraf Zaidi

, “The Best Wall of Defense”

Robert Dreyfuss

, “How to Get Out”

For a collection of The Nation‘s best Afghanistan coverage, see our special page of links, “Afghanistan In Crisis.”