Meh, I think it’s fine and good for countries to specialize and be dependent on each other. Keeps the peace through mutually assured economic destruction. Global upticks in isolationism preceded the World Wars. Also, it just makes sense, because different countries have different resources, and their populations are differently skilled.
He wants to use tariffs (which act like a flat-tax) to lower income tax on the rich. There’s speculation he’s also doing something like the “Mar-a-Lago Accord,” which involves devaluing the dollar (causing inflation). If wages don’t rise with the inflation (which they don’t want), US labor will be more competitive, so people can work in factory jobs with pay analogous to current Chinese factory workers.
He tariffed countries with no people and trade deficits of thousands of dollars, and tariffed Ukraine.