Lol, what happens when other countries start putting tariffs on goods imported from America?
America's economy tanks... that's what.
Unless America heavily invests in R&D that allows them to replace vast amounts of factory workers with robots: It will always have a big trade deficit, as American's are not & never will be prepared to do slave labour (or cut back on imports) and hence won't be able to compete with the likes of China in terms of manufacturing.