SO BEGINS Donald Trump’s tariff roller-coaster, certain to be a stomach-churning journey for the worldwide economic system. He began his first day in workplace with an sudden present of restraint: fairly than slapping hefty new tariffs on different nations, he as a substitute issued a presidential memorandum calling for a overview of unfair commerce practices. It appeared to be a measured begin for Mr Trump—a minimum of on the protectionist entrance, if not his wider programme—prompting aid in authorities workplaces and on buying and selling flooring all over the world. Foreign exchange and shares rallied.