Little under a century ago, an ill-fated law helped spiral the Wall Street crash of 1929 into a worldwide depression. The Smoot-Hawley Tariff encompassed roughly a quarter of all imports, flaring tensions with U.S. trading partners and halving American imports and exports as a result. Caught in the crosshairs, Americans learned the hard way that trade wars are expensive, and today, we ought to be careful deciding with whom to pick them.

In recent weeks, the president sought to impose sweeping tariffs on Mexico, Canada and China, as well as key imports, such as steel and aluminum. While the administration walked back plans to levy 25% duties on imports from Mexico and Canada – paused now for 30 days as both nations brokered deals to tighten border security and crack down on illegal drugs – the president’s aggressive proposals leave big, lingering concerns for American industry and workers.

Indeed, it’s high time for America’s closest neighbors to take the crisis at our border seriously. But no matter our best intentions, tariffs are bad policy. As Sen. Rand Paul put it: “Tariffs are simply taxes. … Taxing trade will mean less trade and higher prices.”

Republicans ought to be clear-eyed about the full, unadulterated impact of tariffs as we work to restore sound fiscal policy to our government.

Blanket tariffs make it more expensive to do business in America, driving up costs for consumers across the board. These aren’t just abstract concerns. Broad-based tariffs could have long-term consequences right in our backyard.

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Consider our state’s 75,000 family farms that sell their crops around the globe, or the hardworking Kentuckians who craft 95% of the world’s bourbon, or our auto industry that relies on global supply chains to support the livelihoods of thousands of workers in the commonwealth.

Tariffs could cost average Kentuckian $1,200 a year

In Kentucky, local storeowners are already hearing about their suppliers’ prices going up. One estimate suggests the president’s tariffs could cost the average Kentuckian up to $1,200 each year. And it’s not just about rising prices here at home.

During the last Trump administration, retaliatory tariffs from trade partners set off a broader trade war that hit wide swaths of American industry, from agriculture to manufacturing to aerospace and motor vehicles to distilled spirits. Already, Canada announced retaliatory measures that take direct aim at Kentucky production, targeting products like peanut butter and whiskey.

Hundreds of thousands of U.S. jobs are tied up, directly or indirectly, in trade with Canada and Mexico. Our neighbors to the north and south buy over half a trillion dollars’ worth of our goods and services each year ‒ including nearly $10 billion in manufactured goods and $300 million in agricultural exports from Kentucky alone.

These economic tailwinds touch virtually every family and every industry.

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International trade is a two-way street

America’s open markets also fuel billions in capital investment from businesses abroad. In Kentucky, more than 60% of all counties are home to at least one international business. These are industrial suppliers, auto manufacturers and makers of consumer goods from across the world that support roughly 100,000 jobs in the commonwealth.

These investments don’t happen on their own. Foreign businesses choose America because they can count on our commitment to free markets and free enterprise. Sudden shifts to protectionism undermine the certainty these companies rely on to do business in the United States.

When we engage with our allies and partners, we unlock new sources of economic strength – lower prices, more choices for consumers and greater innovation. And we ought to remind ourselves that trade is a two-way street.

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Take our work on the United States-Mexico-Canada Agreement under the first Trump administration.

This landmark deal with Canada and Mexico leveled the playing field for American workers, reduced the incentives to ship American jobs to Mexico, and expanded American producers’ access to sell goods to these neighboring markets – including Kentucky-made products like bourbon, cars, aerospace parts and agricultural commodities.

Trade wars with our partners hurt working people the most

That doesn’t mean the system is perfect.

For the adversaries coordinating to threaten America’s security and undermine our interests, economic predation is a weapon. And holding China and other anti-competitive countries accountable for predatory practices that abuse our system should absolutely be an urgent priority. We should continue to push back against unfair competition and shore up critical supply chains.

Nevertheless, preserving the long-term prosperity of American industry and workers requires working with our allies, not against them. Trade wars with our partners hurt working people most. And the president has better tools to protect American workers without forcing our families and businesses to absorb higher costs.  

As the president and Republicans work to undo the damage of the past four years, we ought to strengthen our friendships abroad ‒ and reinforce our allies as pillars of American prosperity and security.

At a time when Americans are tightening their belts, we would do well to avoid policies that heap on the pain.

Mitch McConnell is the senior senator of Kentucky. He is the longest-serving Senate party leader in American history. He is the chair of Senate rules and defense appropriations committees and a senior member of the Senate agriculture committee. This column originally appeared in the Louisville Courier Journal.