The current power-sharing government among factions in Afghanistan will likely be as successful as the one in Iraq during the Nouri al-Maliki period: not very. A viable democracy is only possible if fair elections produce an acknowledged winner and a losing loyal opposition exists -- at least one loyal enough not to fatally undermine the group or groups in power. The political culture of Afghanistan has none of those prerequisites. The last Afghan election was clearly corrupt and therefore perceived as illegitimate, thus rendering it unlikely that any opposition would be loyal. Because of that failed outcome, the United States then arranged that the two electoral antagonists -- Ashraf Ghani, representing the Pashuns, and Abdullah Abdullah, representing other ethnic groups -- would share power, with Ghani becoming president and Abdullah becoming chief executive.
Yet, democratic elections are supposed to have a winner and a loser, and the winner is supposed promulgate policies and endure their critique by the loyal opposition. But as in Iraq during the Maliki period, the various factions trying to govern together in the power sharing agreement cannot agree on a new cabinet, even despite the unforgiving reality that the wheels are coming off the country's security bus. It is yet another case of politicians fiddling g while Rome burns in a faux democracy that has no genuine culture of political compromise. A rash of Taliban suicide bombings has rattled the confidence of the Afghan capital, Kabul, while stepped up Taliban attacks in the countryside have lasted longer in the fall than usual and have disadvantaged Afghan army and police forces. Because of this emboldened rebel activity, the United States will continue to provide Afghan security forces with support from air power even after its ground combat mission allegedly ends at the end of this month. Thus, the United States, after already spending tens of billions of dollars fighting with and training the Afghan security forces, as well as spending oodles on what will become wasted development efforts, will continue to pour money down a rat hole in a lost cause.
In my book, The Failure of Counterinsurgency: Why Hearts and Minds Are Seldom Won, I explore why such counterinsurgency wars are so hard for great powers to win. And it's not like no prior track record in Afghanistan existed to warn the U.S. government of the perils of such armed social work. No foreign power has subdued Afghanistan since before Christ, including three failed attempts by the British in the 19th and early 20th centuries and one more recent debacle by the Soviets in the 1980s.
Historically, sustained democracy has to bubble up from below, with the proper culture of political compromise existing before institutions can govern in a democratic way, not the other way around. Furthermore, democracy has even less of a chance of lasting if a foreign power imposes it by force, especially in countries that have never before had much of a democratic tradition. Also, a distinction exists between mere majority rule -- which can result in a tyranny of the majority, as has happened in Iraq -- and a liberal democracy in which all-important minority rights and the rule of law are guaranteed. Often, for a genuine liberal democracy to sustain itself and flourish over the long-term, a certain societal income level has to be achieved, which fosters the rise of a politically powerful middle class that challenges the entrenched elite. In neither Iraq nor Afghanistan has this level been reached. In Iraq, prosperity was sapped by years of war and international economic sanctions; Afghanistan remains a very poor country.
Thus, keeping about 10,000 U.S. ground troops in Afghanistan, plus the use of U.S. air power, merely makes it more likely that the United States will be drawn back into the conflict to save the non-viable power sharing government from the again rising Taliban. The United States has become enmeshed again in Iraq even without leaving sizeable numbers of troops there after the withdrawal date. Brushfire conflicts in such artificial countries with deep societal cleavages will likely continue to rage, whether or not the United States is entangled in them. If the Taliban didn't learn their lesson by being thrown out of power because of their reluctant sheltering of anti-American terrorists and continue to do so in any future territory they rule, the United States should limit its involvement to occasionally bombing terrorist training camps and infrastructure from the air. Therefore, the United States should withdrawal all remaining ground forces and terminate combat air support for Afghan security forces to avoid getting sucked back into this pointless and endless quagmire that was lost long ago.