Trump told a rally in Port Huron, Michigan, on Sunday that Canada had been "ripping off" the U.S. on trade and that the U.S. had no choice but to impose levies on Canadian goods.

Eleven days before the midterms, Trump quietly reshuffled which Canadian goods face his 50% tariffs, and a trade lawyer says more items were added than removed. The small print may matter far less than a brewing court case that could unravel the whole tariff regime at once.