The president has pitched his trade policies at workers who feel left behind by globalization. But that doesn’t mean trade barriers will revive factories and close income gaps.

Trump has justified tariffs on goods from Canada, the top U.S. export market, by accusing it of failing to stop the cross-border flow of fentanyl, even though U.S. government data shows Canada accounts for only 1% of the fentanyl that enters the United States.

South Africa faces a 30% tariff on its exports to the United States starting next week, a move expected to cost tens of thousands of jobs after the country failed to secure a trade deal before a deadline set by U.