Supreme Court sets up wealth tax battle for Congress

The Supreme Court passed the ball back to Congress on the question of a wealth tax in its decision on Moore v. U.S. last week, a case that implicated trillions of dollars in government revenue and vast swaths of federal law and precedent.

The decision carefully avoided the most wide-ranging questions on taxation raised by the case and kept the overall structure of the U.S. tax system intact in a 7-2 ruling against the petitioners.

But it also kept the door open to a potential ...