President Donald Trump on Friday threatened a 50% tax on all imports from the European Union as well a 25% tariff on Apple products unless iPhones are made in America. The threats, delivered over social media, reflect Trump’s ability to disrupt the global economy with a burst of typing as well as the reality that his tariffs are not producing the sufficient trade deals he is seeking or the return of domestic manufacturing he has promised voters. The Republican president said he wants to...