Yesterday, President Obama defended his new approach to the war in Afghanistan. According to the president, our strategy is to disrupt, dismantle, and defeat al Qaeda and its extremist allies. In order to accomplish this goal, Obama’s strategy indicates we must create a functioning national state there.

Why?

Beltway orthodoxy tells us it’s because extremists will emerge in ungoverned parts of the world and attack the United States. As my colleagues Justin Logan and Chris Preble point out here, there’s reason to doubt whether state failure or poor governance in itself poses a threat.

But responsible leaders would be upfront about the expected costs of our policy: to transform what is a deeply divided, poverty stricken, tribal-based society into a self-sufficient, non-corrupt, stable democracy would require a multi-decade commitment—and even then there’d be no assurance of success.

Why Afghanistan’s form of governance directly implicates America’s security, or why it demands the deployment of tens of thousands of U.S. troops to police it are questions rarely asked let alone addressed.