The Kennedy Center is threatening a longtime jazz musician with a $1 million lawsuit. That came after he pulled out of a Christmas Eve show in protest of the building being renamed to include Donald Trump’s name. The musician, Chuck Redd, has led that holiday event for nearly 20 years and says the name change crossed a line for him. The Center’s president, Richard Grenell, calls it a political stunt and says real artists should perform no matter what. So now a national arts nonprofit is trying to financially punish an artist for opting out on principle. The government telling artists to fall in line or else?

The Kennedy Center is threatening a longtime jazz musician with a $1 million lawsuit. That came after he pulled out...