AFTER A TRIP to France for the centenary of the end of the first world war, President Donald Trump quickly turned his Twitter feed over to trade-related tirades. On November 12th he opined that “Trade must be FREE and FAIR!” The next day he complained about French tariffs on American wine, concluding “Not fair, must change!” A day later came another reminder of the brittleness of transatlantic trade relations, when reports emerged that Mr Trump was meeting his officials to discuss an investigation launched in May into whether imported cars and car parts threaten America’s national security. If it concludes that they do, he can impose whatever trade restrictions he wants.
The idea that importing cars from close allies threatens America is barely plausible. In reality the investigation is intended to strong-arm trading partners into concessions. The tactic met with some early success. In July Jean-Claude Juncker, the president of the European Commission, and Mr Trump agreed to…
