As Sino-American trade relations have improved in recent weeks, President Trump has turned up the heat on his European allies. But it is U.S. businesses and consumers that could end up burned.

The White House is in the final stages of deciding if it will slap 100% tariffs on $2.4 billion worth of French wine and luxury goods. The European Union has said it stands with France and “will respond” if the U.S. follows through. Europe’s trade commissioner Phil Hogan and U.S. Trade Rep. Robert Lighthizer will discuss the topic this...