Retired General Stanley McChrystal: Anywhere you have undergoverned or ungoverned areas, organizations like al Qaeda have a tremendous opportunity to get a foothold. And when they can get a foothold, they can start to operate and spread from there.

Foreign Affairs: So what do you do with places like Mali and Yemen?

Well, you can’t solve all of them. You certainly don’t want to put Western forces in all of these countries. The initial reaction that says, “We will simply operate by drone strikes” is also problematic, because the inhabitants of that area and the world have significant problems watching Western forces, particularly Americans, conduct drone strikes inside the terrain of another country. So that’s got to be done very carefully, on occasion. It’s not a strategy in itself; it’s a short-term tactic.

It seems like the methods you pioneered in Iraq have been embraced by the U.S. government and the American public as a general approach to managing small-scale irregular warfare, and doing so in a way short of putting lots of boots on the ground or walking away entirely. Some would argue that this is the true legacy of Stan McChrystal — the creation of an approach to counterterrorism that is halfway between war and peace, at such a low cost and with such a light footprint that it’s politically viable for the long term in a way that war and disengagement are not. Do you disagree?

I question its universal validity. If you go back to the British tactics on the North-West Frontier, the “butcher and bolt” tactics, where they would burn an area and punish the people and say, “Don’t do that anymore,” and simultaneously offer a stipend to the leader while saying, “If you will remain friendly for a period of time, we’ll pay you” — that approach worked for a fair amount of time. It managed problems on their periphery. But it certainly didn’t solve the problems.

The tactics that we developed do work, but they don’t produce decisive effects absent other, complementary activities. We did an awful lot of capturing and killing in Iraq for several years before it started to have a real effect, and that came only when we were partnered with an effective counterinsurgency approach. Just the strike part of it can never do more than keep an enemy at bay. And although to the United States, a drone strike seems to have very little risk and very little pain, at the receiving end, it feels like war.

Americans have got to understand that. If we were to use our technological capabilities carelessly — I don’t think we do, but there’s always the danger that you will — then we should not be upset when someone responds with their equivalent, which is a suicide bomb in Central Park, because that’s what they can respond with.