Specifically, they welcome Mr Trump’s crusade to redraw the rules of international trade but know from experience just how porous tariffs can be. What is needed, they say, is much stricter enforcement at the border to prevent foreign companies from dodging levies.

As Donald Trump’s tariffs send markets into a tailspin, pressure is mounting on the president to speed up his main proposal for juicing the economy: a sweeping tax bill.

Head-spinning moves are becoming routine in what’s been a scary ride for investors as the president tries to remake the country and world through tariffs and other policies.