Few world leaders have caused such universal consternation, even before they formally accepted their office, as President Donald Trump has. Much of this apprehension arises out of his past record of extreme aggression whenever he perceives that American interests are hurt, leading to a lot of sabre-rattling and chest thumping. The more worrisome part lies in his weaponising of tariff protect the American market against importers, until they zip open their markets to him or toe his political line.