Trump, after all, doesn’t truly have tariff power: The Constitution gives Congress the sole power of taxation. But Congress has delegated that authority to the president, which means Congress can also take it away. Democrats who control the House of Representatives are presumably ready and willing to cut off Trump’s authority as soon as it’s feasible. That could happen if Democrats retake the Senate in 2020, but it could also happen sooner if Senate Republicans, faced with a decision between party loyalty and helping Congress reclaim its power, choose the former.

Trump should be worried.

“I’m more of an ‘open-the-markets’ kind of guy rather than look for ways to close those markets,” Sen. Roy Blunt (R-Mo.) said this week. Many of his colleagues have made similar comments of late.

Disempowering the president would probably be very unpopular with Republican primary voters. But would it be less popular than stripping voters of their jobs and incomes? Studies suggest a 5 percent tariff on Mexican goods could cost more than 400,000 jobs at home, while another estimate suggests that tariffs on Chinese goods could end up costing every American household roughly $500.