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