U.S.—A number of Democratic candidates have seized on a new initiative to make Americans feel safer: a mandatory buyback. “There are a number of ideas out there that just make people upset when they’re said out loud,” said presidential candidate Beto O’Rourke. “It’s time to take those ideas off the street. That’s why it’s past time for a mandatory free speech buyback.” The idea that the government can take away people’s rights if it just compensates people for them has a long history as a thing that Democrats have proposed but not thought too deeply about. The current proposal is...