It was announced on Thursday November 21, 2013 that Washington and Kabul had reached an agreement to allow limited American training forces and anti-terrorism personnel to remain on after the scheduled departure of American combat personnel from Afghanistan in 2014. The deal has yet to be approved by the Grand Council or Loya Jirga, which has the power to approve or reject a deal. Afghani President Hamid Karzai is using his weakness as a strength to attempt to manipulate Washington into granting more concessions to him by making the deal subject to the Loya Jirga.
The Afghanistan insurgency is really an ethnic war between the Kabul government, which is based on the former Northern Alliance of Tajik and Uzbek forces against the Afghani Taliban, a Pashtun (Pathan) force. The Pashtun is a tribal group straddling the border between Afghanistan and Pakistan. They are by far the largest ethnic group in Afghanistan and the largest ethnic group in the North West Frontier Province, the Pakistani province that borders on Afghanistan. They are also the third largest ethnic group in Pakistan after the Punjabis and Sindhis and ahead of the Baluchis. The Pashtun are a warrior culture based on a code of Islam, loyalty to guests, and resistance to outsiders. They have resisted Western forces since the British first reached the area in the 1830s. Usama Bin-Ladin's Al Qaeda was the guest of the Taliban and perceived by them to be fighting for Islam against the infidel foreigners.
Ending the war in Afghanistan is dependent on reaching a diplomatic solution with elements of the Taliban that will exclude Al Qaeda. Unfortunately for Washington, Islamabad sees controlling access to the Taliban to be in its interest. The war has provided Pakistan with billions of dollars in economic and military aid since 2001 that the Pakistani military has used to help fund its war in Kashmir, which it really cares about, against India. India has supported the Kabul government as a means of balancing Pakistan by forcing it to concentrate on Afghanistan as well as Kashmir.
America's national interest in Afghanistan is minimal. The rationale for backing the Northern Alliance in the fall of 2001 was to prevent Al Qaeda from using Afghanistan as a sanctuary and to capture or kill Bin-Ladin. Bin-Ladin is now dead and most of Al Qaeda's senior leadership has been killed or captured. There is no shortage of failed Muslim states in the Middle East, North Africa, and South-East Asia that can serve as alternative sanctuaries for the remnants of Al Qaeda. In the late 1990s American pressure forced Al Qaeda to move from Sudan to Afghanistan--the net effect was to make it that much less accessible to American forces. Somalia, Mali, Yemen, and parts of Indonesia and the Philippines can all serve as alternative sites for Al Qaeda or similar Islamist terrorist groups.
Meanwhile the war in Afghanistan risks the stability of Pakistan, a country that is much more strategic and populous than Afghanistan as well as being a nuclear weapons state. Better to cut our losses as soon as possible rather than keep funding the treacherous and unpopular Karzai regime.