Facebook banned deepfakes. But there’s a more menacing type of video out there.

FACEBOOK BANNED the highly altered, algorithmically generated videos known as deepfakes from its platform this week. But what may be a bigger problem for our politics has a less menacing name: cheapfakes.

There’s no question deepfakes are frightening. It’s possible for anyone with some money to spare to use machine learning to simulate an individual saying something they never said or doing something they never did — and difficult for those rooting out the dissimulation to stay ahead. The Post reports that start-ups are selling images of false faces to...