Democrats running for president next year have worked hard to differentiate themselves from President Trump on issues such as immigration, tax cuts and health care. When it comes to trade, that hasn’t been so easy.

Trump, after all, came to office as a fierce critic of U.S. trade policy, arguing that previous administrations had been duped into signing free-trade agreements that had cost Americans millions of manufacturing jobs.

“I pledge to never sign any trade agreement that hurts our workers or that diminishes our freedom and independence,” he said to enthusiastic applause in his nomination speech at the 2016 Republican National Convention.

At times, Trump’s rhetoric on trade has sounded pretty much indistinguishable from the most liberal Democrats. And since taking office Trump has veered sharply away from traditional Republican policy on trade, through a series of tariffs and trade wars that have upended relations with the most important U.S. trading partners.

“It’s like Donald Trump has co-opted Democratic trade policy,” says Dan Ikenson, director of the trade policy center at the libertarian Cato Institute.

Democrats have long been seen as the party of the working class and labor unions, and many shared a strong skepticism about trade agreements.

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