Exiting Afghanistan: Ending America's Longest War

Bottom line: After succeeding in its initial aims, U.S. involvement in Afghanistan spiraled into a doomed, expensive and unnecessary attempt at nation building. The time has come for the U.S. to withdraw from Afghanistan and let regional powers take over.

Afghanistan's history of weak governance makes long-term peace unlikely.

The country has spent "nearly 40 years [in] almost continuous civil war, often with the support of one or another foreign patron." Ethnic and economic tensions are high. And the country's poor economic circumstances have yielded supply of able-bodied young men, increasing the likelihood of further conflict.

Despite this history, U.S. officials engaged in an ill-advised and unnecessary attempt at state building.

The U.S. first entered Afghanistan in 2001 in order to destroy Al-Qaeda and retaliate against the Taliban government. It had accomplished each of those objectives within a year. But the government soon turned its attention to building a stable government in Afghanistan.

After almost two decades, the United States has wasted time and money trying to suppress Taliban support, train Afghan security forces, and purge corruption from the government. Essentially, the United States moved from successful counterterrorism efforts to an unsuccessful counterinsurgency.

The U.S. must withdraw from Afghanistan because it's what's best for us -- not them.

There is no guarantee that U.S. withdrawal from Afghanistan will lead to increased stability in the country. But that's not the point. U.S. involvement in Afghanistan has drawn on long enough, and with no measurable results.

At this point, "the case for leaving…turns on saying enough failure is enough, and that Afghanistan needs to move toward a political outcome it can maintain without eternal U.S. sponsorship." If, as some critics say, a U.S. exit would create a "vacuum" in the region, it will be up to Afghanistan and surrounding countries to deal with.

Read the full explainer here.