The largest business lobbying group in America is declaring war on President Donald Trump’s trade agenda.

The US Chamber of Commerce, an advocacy group that represents more than t3 million American businesses, launched a new campaign on Monday designed to persuade policymakers and the public that the Trump administration’s increasingly aggressive trade policies represent a huge threat to the American economy.

The Chamber released an interactive graphic that maps out how Trump’s trade conflicts with China, Europe, Canada, and Mexico could affect each state in the country in the coming months. It details how many of each state’s exports to foreign countries are vulnerable to retaliatory tariffs against Trump’s tariffs — and warns that they could cause millions of job losses.

“Tariffs are beginning to take a toll on American businesses, workers, farmers, and consumers as overseas markets close to American-made products and prices increase here at home,” US Chamber President Thomas Donohue said in a statement. “The administration is threatening to undermine the economic progress it worked so hard to achieve.”

The Chamber has criticized Trump’s protectionist approach — using tariffs, or border taxes, to shield American industries from foreign competition — in the past, but the new campaign intensifies its agenda to whip up resistance to Trump’s policies.

And it comes at a time when Trump’s own party is running out of patience with the way he’s picking fights with the US’s most important trading partners.

“I’d like to kill ’em,” Finance Committee Chair Orrin Hatch (R-UT) said of Trump’s tariffs in a recent interview with Politico.

Hatch, along with other lawmakers in both parties, is considering legislation that would limit Trump’s powers to unilaterally issue tariffs and put a leash on his America First trade vision. Concerned that trade wars could dampen the economy’s pace before the midterm elections in November, they’re contemplating drastic measures to curb one of Trump’s signature policy priorities.

Trump is picking a lot of fights — and they could spiral out of control

In the past few months, Trump has begun to roll out sweeping, controversial tariffs on exports from a number of the world’s most powerful economies, many of whom are allies and friends of the US. And many of those countries have chosen to retaliate with tariffs of their own.

Canada is putting tariffs on US steel, aluminum, whiskey, toilet paper, washing machines, and motorboats. Mexico is targeting US pork, steel, cheese, bourbon, and apples. Europe is hitting bourbon, peanut butter, and Harley-Davidson motorcycles. China is imposing tariffs on soybeans and other agricultural goods.

Currently, trading partners are hitting hundreds of billions of dollars worth of US goods with tariffs. But Trump still has more tariffs in the pipeline and he’s also threatened to retaliate against other countries’ retaliations. The Financial Times’s chief trade correspondent Shawn Donnan says that a $1 trillion trade war in the future is “not wholly implausible.”

All of this is causing enormous anger and anxiety among the pro-free trade crowd in Washington. Lawmakers in both parties have tried in vain to persuade the president to reconsider using protectionism to boost the economy.

“Individual senators have met with the president, including me. The Ag committee met with him, the Finance Committee met with him. And there’s nobody for this,” Sen. Pat Roberts (R-KS), the Agriculture Committee chair, told Politico.

Sweet-talking hasn’t worked, so Republican lawmakers are now considering hardball tactics. Hatch and others are working on a bill in the Senate Finance Committee that would limit Trump’s powers to issue tariffs on foreign steel and aluminum imports. Separately, Republican Sens. Bob Corker (TN) and Pat Toomey (PA) are also considering adding an amendment to an upcoming farm bill that could do the same thing. The Chamber of Commerce’s campaign could add to momentum for any such bill.

The Chamber is also getting serious about pushing a pro-free trade agenda in the upcoming elections. According to Reuters, they’ve already poured money into Republican primaries to back pro-free trade candidates and they expect to spend millions ahead of the November elections.

Midterm elections already tend to be tough for the party that controls the White House. Infighting in the GOP over what kind of trade policy is right for the party could make that contest even harder.