The war in Afghanistan — the war that President-elect Barack Obama pledged to fight and win — has become an aimless absurdity. It began with a specific target. Afghanistan was where Osama bin Laden and al-Qaeda lived, harbored by the Islamic extremist Taliban government. But the enemy escaped into Pakistan, and for the past seven years, Afghanistan has been a slow bleed against an array of mostly indigenous narco-jihadi-tribal guerrilla forces that we continue to call the "Taliban." These ragtag bands are funded by opium profits and led by assorted religious extremists and druglords, many of whom have safe havens in Pakistan.
We know what the mission used to be — to kill or capture Osama bin Laden and destroy his al-Qaeda command. But once bin Laden slipped away, the mission morphed into a vast, messy nation — building effort to support the allegedly democratic Karzai government. There was a certain logic to that. The Taliban and al-Qaeda can't base themselves in Afghanistan if something resembling a stable, secure nation-state exists there. But the mission was also historically implausible: Afghanistan has never had a strong central government. It has been governed for thousands of years by local and regional tribal coalitions. The tribes have often been at one another's throats — a good part of the current "Taliban" uprising is nothing more than standard tribal rivalries juiced by Western arms and opium profits — except when foreigners have invaded the area, in which case the Afghans have united and slowly humiliated conquerors from Alexander the Great to the Soviets.
History is not at all on our side, as Michael Crowley discusses in more detail(via Ezra Klein):
Afghanistan is like a Chinese finger trap: The harder you try to solve it, the more it constricts you. Ask the Russians. In 1979, the Soviet Union sent military forces to install a pro-Soviet government in Kabul. At its peak in the country, the Red Army numbered some 140,000. But, after ten years of inconclusive fighting, 15,000 dead, and tens of thousands more wounded, the battered Soviets mounted a humiliating retreat--one that probably helped speed the collapse of their empire. ("They've already repeated all of our mistakes," one former Soviet general from the Afghan campaign recently said to The New York Times of the U.S. occupation.) Or ask the British. More than a century earlier, the United Kingdom dispatched a huge army to Afghanistan from India to secure it against Russian influence. That adventure, too, was a disaster, ending in a retreat of 16,500 troops and civilians through the Khyber Pass into Pakistan. Only one survivor made it--his life spared by the Afghans so he could recount the ghastly tale for others.
As Klein also mentions, the the most maddening problem when it comes to securing Afghanistan is Pakistan. And in that respect, the situation has only gotten worse. Another thirty or fifty or hundred thousand troops may do wonders for bringing security to more remote regions of Afghanistan, but we face an intractable problem in the fact that the Taliban can cross the border into Pakistan at will. Pakistan is presently the home of an even more powerful Taliban that now appears willing to challenge the government of Pakistan directly, and Pakistan itself faces worsening relations with India thanks to the Mumbai attacks last month.
So far I've seen nothing that indicates that Obama is considering or anticipating backing away from the general nation-building exercise we presently have going on in Afghanistan. I do not see Obama as the type of President to continue investing heavily in a war that can't be won, but the problem is there appear to be very few establishment figures calling for anything other than a greater commitment to Afghanistan, and a majority of Americans seem to agree that the war is still winnable. If in fact the mission in Afghanistan becomes untenable such a conclusion will not be clear for some time, and it will be some time still after that before a clamor to bring the troops home. And unfortunately unlike in Iraq, Pakistan remains a safe harbor for Al Qaeda, an organization that continues to pose a threat to us and other western nations to a degree that can't simply be ignored.