A federal appeals panel on Thursday appeared skeptical of U.S. President Donald Trump's argument that a 1977 law historically used for sanctioning enemies or freezing their assets gave him the power to impose tariffs.

Last Thursday, on the same day that Trump blitzed the world, yet again, with a new round of tariffs on a broad range of goods, a specialized appeals court in Washington, D.C., inched closer to a definitive pronouncement on whether the President can legally make such sweeping economic demands—on a whim, whenever he feels like it.