There is no easy way out of Afghanistan. The problem starts with India and Pakistan and ends only if peace can be found between them.
India and Pakistan have gone to war four times. In 1947, they fought a long and intense battle over Kashmir. In 1965, they fought another war over Kashmir. In 1971, they fought during the Pakistani civil war that resulted in the creation of Bangladesh. Finally, in 1999, they fought in the Siachen glacier region of Kashmir. Since then, they have successfully tested nuclear bombs and are presumably capable of launching nuclear-armed missiles at each other. Few other conflicts, with the possible exception of the Palestinian-Israeli dispute, have proved to be as intractable.
Over the years, Pakistani decision-makers have over-estimated the desire of Kashmir to be a part of Pakistan and have underestimated Indian military power and its likely responses to force. Throughout, Pakistan has held an immutable belief in its own cultural superiority to India. Now, Pakistan looks forward to the U.S. end game in Afghanistan.
In the Pakistani military's view, the international community will leave Afghanistan as President Obama has promised. When that happens, Pakistan feels that it must install a friendly regime in Kabul, one that will expel the pro-Karzai Indian advisors and provide a potentially friendly area to the rear of Pakistan in the event of another major war with India. This is the Pakistani idea of "strategic depth." The most likely candidate for a friendly government is the Pashtun-dominated Afghan Taliban. However, Pakistan is also battling a civil war with the Pakistani Taliban, also composed of Pashtuns. In Pakistan's eyes, the Pakistani Taliban is a dangerous rebel, while the Afghan Taliban is the next government of Afghanistan.
When the U.S. leaves, Karzai's government will face enormous pressure from the Afghan Taliban, supported by the Pakistani intelligence service. India will do what it can to support Karzai. If Karzai's government falls, Afghanistan returns to where it was in 1996 when the Taliban took control of the country. If Karzai remains in power, his government will probably not control Pashtunistan, the swath of land in Afghanistan and Pakistan inhabited by the Pashtuns, and likely will not control much of the Tajik-controlled north. In either case, civil war looms if the ancient hatred between the Tajiks, the Hazzari, and the Pashtun escalates into widespread violence.
Add to this inflammatory mix the potential mineral wealth recently discovered in Afghanistan. The Chinese are probably the only ones willing to take a risk in Afghanistan to get at the resources. When it comes to corruption, Chinese firms have not been troubled by partnerships with regimes that engage in human rights abuses. Thus, as long as it gets the minerals and is not troubled by extremists in its own Islamic regions, China will probably tolerate any regime. Apparently, India and China have had some talks about joint ventures about mining in Afghanistan, but the relationship between China and Pakistan has been close as well. China could also play India against Pakistan for its own economic and strategic advantage.
The upshot for the U.S. and its allies is this: Settle the Pakistan-India conflict. Until the two countries can live in reasonable security and peace with each other, their competition for power and influence will perpetuate the chaos in Afghanistan. That peacemaking assignment will be long and challenging. If the India-Pakistan relations are normalized, however, Afghanistan might peacefully evolve to a loose federation guaranteeing significant regional autonomy to the Pashtuns, Tajiks, and Hazzaris in exchange for agreements not to support terrorists or opium production. In the absence of peace between India and Pakistan, chaos will reign in the region.