Some of the questions Professor Miller addresses are concerned with proportionality, a notion whose complexities are only beginning to be appreciated. My modest ambition in this comment is to try to sharpen these questions and provide some assistance in thinking about them.

The United States has had a moral duty, at least since the end of 2010, actively to pursue negotiations with the Taliban and Pakistan to achieve a political settlement, conceding control of the Pashtun countryside to the Taliban.

While Professor Miller claims that just war theory cannot "provide sufficient guidance" on the question of Afghanistan, his concerns actually fall squarely within its purview, and do not suggest its inability to critique proposals to prolong the American and NATO presence in Afghanistan.