It’s Much Bigger Than Afghanistan: US Strategy for a Transformed Region by Barnett Rubin, War on the Rocks
… It is time to recognize that the United States might be able to maintain an open-ended military presence in Afghanistan or stabilize the country, but not both. A permanent military presence will always motivate one or more neighbors to pressure the United States to leave by supporting insurgents — and forestalling stabilization. Currently, Pakistan, Iran and Russia — which together control access to all usable routes to landlocked Afghanistan — are trying to exert such pressure.* Precipitous withdrawal without a settlement, of course, could lead to even more violence.
Such a settlement would be as much with Afghanistan’s neighbors as the Taliban, but U.S. strategic thinking about the region is caught in a time warp. Washington still conceives of the region as a theater of the war on terror, and forms bilateral policies toward Afghanistan and its neighbors on that basis. The economic growth of China and India, however, has changed the stakes in the region. Both the apparently permanent U.S. military presence and the rise of the self-proclaimed Islamic State have changed the region’s perception of the Taliban…
As what everyone, including the United States, thought would be a time-limited counter-terrorism intervention in Afghanistan has morphed into a permanent outpost, neighboring states view the U.S. presence in Afghanistan as geostrategic. In their view, the United States could use its bases and other military assets in Afghanistan against them under the banner of counter-terrorism[RE1] . The United States said support for terrorism was one of the rationales for the overthrow of Saddam Hussein. It could easily do so again to justify intervention in Iran, classified by the U.S. State Department as a leading state sponsor of terrorism, or Pakistan, where Washington fears nuclear materials or weapons could fall into terrorist hands. Russia also suspects that the U.S. may use counter-terrorism for broader purposes…