How Do We Know Deterrence Works Against North Korea? Because It Already Does.

Yonhap News/Newscom via ZUMA

I want to make a quick point that’s pretty obvious, I guess, but that hasn’t been getting much attention. It’s this: North Korea and the United States have been successfully practicing mutually assured destruction against each other for more than half a century. It’s not the same as MAD between the Soviet Union and the US during the Cold War, in which the threat on both sides was the same—nuclear armageddon—but it’s been effective nonetheless:

  • South Korea. The United States keeps about 30,000 troops along the North-South Korea border. This is not because South Korea needs the extra manpower. They have 600,000 active troops and several million more reserves. Our troops are there as a tripwire. If North Korea ever launched an attack, it would kill lots of American troops, guaranteeing that America would respond and North Korea would be wiped off the map.
  • North Korea. The DPRK maintains an immense amount of artillery along its border with South Korea. Since Seoul and other large cities are only 30 miles from the border, North Korea can immediately inflict tremendous loss of life on South Korea if it’s ever attacked.

So: North Korea can’t attack because they risk being destroyed by an American response. South Korea can’t attack because they risk losing thousands or millions of lives in a North Korean response.

This is a ghoulish standoff. But despite the alleged madness of North Korea’s leaders, it’s worked. Since 1953 there have been hundreds of fracases and dozens of more serious incidents along the border, but thanks to the grisly logic of deterrence none of them have turned into anything more serious. If North Korea develops the means to launch nuclear missiles at the United States, there’s no reason to think it won’t continue to work. The weapons are different, but the fundamental calculus isn’t.