By the time 2010 came to a close 1370 Americans had died in the Afghan theater. Of those, 1309 were killed in Afghanistan, 15 in Pakistan, and one in Uzbekistan, and 45 others died elsewhere of their wounds. Nearly 500 died last year alone.

For what did they die?

Until last month these numbers were but abstract statistics to me. There were names attached to each one, of course, and the Pentagon issued a standard four-sentence press release per death. But while I have family members and friends in the military and friends who have served in Afghanistan and Iraq, thankfully none have died in combat. From my perspective, the long list of unfamiliar names -- available online, like most everything else in life -- could have been a few pages from the phone book or the results from a marathon.

In December one of those names took on special significance. A Marine Corps corporal was killed in Helmand. He was one of ten claimed by that province in December.

I didn't know him, but he was a favorite relative of a very good friend. The family was close, with regular reunions so even extended relationships remained tight. His death broke up my friend.

That helped turn a statistic into a person.

Death is an inevitable cost of war, and war sometimes is a terrible necessity. But why Afghanistan in 2010? More than nine years after the 9/11 terrorist attacks, precisely why did this young man die?

The U.S. originally intervened in Afghanistan to destroy al-Qaeda and overthrow the Taliban, which had hosted Osama bin Laden. That mission was accomplished long ago: al-Qaeda was weakened and dispersed, the Taliban was ousted and punished, and other governments learned the risk of hosting anti-American terrorists.

Administration officials still cite the need to combat al-Qaeda, but it has found an even more hospitable haven in neighboring Pakistan, where the intelligence service long has played a double game. Moreover, much of the Taliban, which is fractured like most politics in Afghanistan, likely would not welcome back a group guaranteed to again bring down Washington's wrath. Today the U.S.-led war may be -- in fact, probably is -- creating more terrorists than it is killing.

Some analysts hold up the fragility of Pakistan as a reason to stay in Afghanistan. However, the war itself is destabilizing that perpetually unstable nation. If the U.S. was not attempting to create a friendly regime in Kabul, it would have less need to press Islamabad to crack down on the Taliban's Pakistani allies. Pakistan's future would be difficult in any case, but ending American participation in the war would ease the Islamabad government's task.

The prospect of a regional struggle for influence in Afghanistan leads some policymakers to advocate a continued U.S. presence. Yet that competition already is ongoing, if somewhat muted. Whether or not American forces are present, Afghanistan is going to be a regional battleground for Pakistan, India, Iran, and Russia. The U.S. has little at stake in that struggle and should leave the conflict to others, avoiding the crossfire.

Credibility is another argument. To leave would be to admit defeat. And withdrawal would reduce the belief of potential adversaries that Washington has sufficient stamina to win and belief of potential friends that they can rely on America.

Undoubtedly there is truth to this contention, but the risk to credibility is best assessed before intervening in conflicts and setting unrealistic, even extravagant objectives. America's credibility will suffer an even greater hit if the U.S. sticks around longer before eventually leaving. And how many lives should be sacrificed for "credibility" when the original objective is no longer thought to warrant the high cost of staying?

The most appealing argument for remaining in Afghanistan is humanitarian: After nearly four decades of conflict, the Afghan people deserve to live in a free and prosperous society. And they do. But that has little to do with America's presence.

Military intervention is a poor means of achieving humanitarian ends. Outside military intervention is rarely an effective tool of nation-building. That the U.S. is well-intentioned matters little to most Afghans who are fighting -- less for the Taliban and more against America and its allies.

When I visited Afghanistan last year, one U.S. consultant said I should imagine the war from an Afghan perspective: what would I think if another nation invaded my country, imposed an unpopular, corrupt government on my community, overturned traditional mores of my culture, arrested my friends and relatives, and sporadically killed my neighbors.

There is little support for the Taliban in many parts of Afghanistan. But the corrupt, ineffective Karzai government often is equally if not more unpopular. Afghans told me that the U.S. should not send in the Afghan National Police, since its activities -- often robbing and terrorizing the local population -- actually create Taliban. Allied personnel had little better to say about the ANP.

Leaving is no panacea. There are liberal Afghans who want to build a free society and fear for their future after an American departure. But the U.S. is incapable of remaking Afghanistan, at least at reasonable cost in reasonable time. It is one thing to ask patriotic Americans to die to protect America. It is quite another to send them to die in a Quixotic quest to "fix" other countries.

Afghanistan has become Barack Obama's war. More Americans have died since he was inaugurated on January 20, 2009 than before. He says he intends to begin withdrawing U.S. forces this year, but virtually no one in or out of government believes him.

Withdrawal is one promise he should keep.

Why did my friend's loved one die? I wish I had a satisfactory answer for her. It certainly wasn't to defend America or stop terrorism. It wasn't to stabilize a perpetually unruly Pakistan or Central Asia. It wasn't to sustain America's credibility, which has survived worse challenges. It wasn't to bring democracy to Afghanistan.

As far as I can tell, it was just "because."

It is time to say no more. No more unnecessary wars for dubious purposes. No more painful human sacrifices in arcane geopolitical games.

Before another American dies the president should begin bringing home U.S. forces. Nine years is enough. It is time to leave the Afghanistan war to the Afghans.