President Trump thinks he’ll win a trade war against countries that sell steel and aluminum to the United States. He’s in for a surprise. In response to tariffs Trump announced last week, the European Union has prepared retaliatory measures to hit Trump where it hurts: purple states such as Wisconsin (with a tariff on Harley-Davidsons) and Florida (orange juice), plus Senate Majority Leader Mitch McConnell’s home state, Kentucky (bourbon). But Trump wouldn’t just be hit by Europe. He’d be hit across the U.S. in November with ads, starring Republican politicians and local business leaders, that blame him for raising taxes and killing jobs.

Since Trump announced his tariff plan on Thursday, Republican lawmakers have excoriated it. They’ve called it a “huge job-killing tax hike” that would wipe out what families gained from tax reform. Conservative economists and business groups say the tariffs jeopardize 5 million jobs at companies that would have to pay more for steel and millions more jobs in industries that would be targeted for retaliation. The goal of these warnings is to change Trump’s mind. But if he goes through with his plan, as he’s promised to do, the dire predictions will be replayed in this fall’s elections.

Scott Walker, the Republican governor of Wisconsin, says Trump’s tariffs would hurt multiple industries in his state, from motorcycles to beer to aluminum foil. “We’ve heard from Wisconsin employers, whether that’s Harley-Davidson, MillerCoors, Seneca Foods,” Walker told reporters Friday. “It could have a devastating impact. … You’re talking about potentially thousands of employees that could be laid off, and those products could be produced in places like Canada.” Ron Johnson, Wisconsin’s Republican U.S. senator, says Trump’s tariffs would amount to “higher taxes” on people and companies in the state. “We’re a big manufacturing state. We use a lot of aluminum in beer canning, but also steel in manufacturing.” says Johnson. When President Bush tried steel tariffs 16 years ago, Johnson recalls, “We lost an awful lot of jobs.” (Bush, facing international and domestic political pressure, scaled back his tariffs before the 2002 midterms.)

Kim Reynolds, the Republican governor of Iowa, worries about the second stage of a trade war. “Our farmers are the first target,” she reminded her constituents at a press conference Monday. “They’re already talking about the impact on soybeans in China and how they will retaliate.” If NAFTA were to unravel, she warned, “The impact that would have on our state … would be devastating.” Joni Ernst, the state’s junior Republican senator, agreed. “The easiest target for other countries is always agriculture,” Ernst told reporters. “It would come back on our growers, our farmers, our ranchers.”

Pennsylvania’s Republican senator, Pat Toomey, says Trump’s plan “will increase costs on American consumers, cost our country jobs, and invite retaliation from other countries.” Charlie Dent, one of the state’s Republican congressmen, says the aluminum tariffs would hurt “companies in Pennsylvania, like the Hershey Company, that rely on aluminum as part of their packaging and manufacturing process.” Ohio’s top two Republicans, Gov. John Kasich and Sen. Rob Portman, caution that the tariffs could impose “higher prices” on consumers and “hurt the automakers and the other users of steel” in Ohio’s manufacturing industries.

If Trump goes through with his plan, Democrats running for office in Arizona will quote Republican Sen. John McCain, who warned on Friday that the tariffs would “hurt American workers and consumers.” Democrats in Texas will quote Republican Sen. John Cornyn, who fretted that retaliation from countries slammed by the tariffs would “devastate our agricultural communities.” Democrats in South Carolina will use excerpts from Republican Sen. Lindsey Graham’s Sunday interview on Face the Nation. “BMW makes more cars in Greenville, South Carolina, than any plant in the entire BMW family,” Graham pointed out. “Thirty-two percent of the tires exported from the United States come from South Carolina. This tariff on steel is going to hurt them.”

In purple states where Republican leaders haven’t spoken out, business leaders will be quoted instead. In Michigan, it’ll be the automakers, whose stock valuations fell 3 to 4 percent after Trump announced his tariffs. (One analysis says the Bush tariffs cost Michigan 30,000 jobs.) In North Carolina, it’ll be pork and poultry industries, which rely on exports to Canada, Mexico, and China. In Virginia, it might be the aerospace industry, its supply chain disrupted by direct or retaliatory effects on steel parts. In Minnesota, one company has already postponed raises for its employees, citing the risk of losses from the tariffs. That kind of story inverts the GOP’s feel-good message of corporate tax cuts trickling down to workers.

That’s the bad news for Republicans. The good news is that Trump hasn’t yet implemented the tariffs. There’s time to turn him away, and free-trade enthusiasts are scrambling to devise an exit ramp. The Republican scare quotes about tax hikes and job losses, like the ghost of Christmas yet to come, are meant to show him a world of pain that can still be averted. But if Trump is too stupid or stubborn to heed those warnings, they’ll haunt him. The “Trump tax” will be blamed for price increases, layoffs, and companies leaving the United States. And the next time a Republican president is mocked for launching a dumb and costly war, it won’t be Bush’s war. It’ll be Trump’s.