Had we left Japan, what would have happened in that country and in Asia generally? Had we left South Korea, would it be the vibrant democracy, and economic power, that it is today — or would it have become like the northern half of the Korean peninsula, the world’s largest concentration camp? Had we left Germany by 1950, what would have happened to Europe during the Cold War? We did leave Vietnam, and communists imposed a reign of terror there and committed genocide in Cambodia.

American troops around the globe are the greatest preservers of liberty and peace in the world.

To return to our original analogy of cities without police: Thinking that we can retreat from the world and avoid its subsequent violence and tyranny is like thinking that if the police go on strike in Chicago, the suburbs will remain peaceful and unaffected.

We have no choice but to be the world’s policeman. And we will eventually realize this — but only after we and the world pay a terrible price.