Canada has no nuclear weapons. After Trump’s Greenland threats, should it?

OTTAWA AND WASHINGTON, D.C. — The U.S. Supreme Court ruled on Friday that the emergency authority that U.S. President Donald Trump relied on to impose sweeping tariffs on Canada “falls short” and said the president violated federal law when he imposed the trade barriers. The decision, which was written by U.S. Supreme Court Chief Justice John Roberts, was a 6-3 ruling. Last year, Trump imposed tariffs on countries around the world using a law meant for national emergencies called the International Emergency Economic Powers Act or IEEPA for short. The justices upheld a lower court’s...