At a rally in Louisville on Monday, President Donald Trump sang the praises of "the great 19th century statesman" Henry Clay, the former Speaker of the House, U.S. Senator and Whig Party co-founder.

"Henry Clay believed in what he called the 'American system,' and proposed tariffs to protect American industry and finance American infrastructure," Trump said. "Like Henry Clay, we want to put our own people to work... Clay was a fierce advocate for American manufacturing. He wanted it badly, he said, very strongly, free trade... He knew all the way back, early 1800s, Clay said that trade must be fair, equal, and reciprocal. Boom."

Experts say that Trump's assessment of Clay's belief that the country would prosper when industry at home grew is correct, yet Clay's ideas weren't based on helping American workers. In that sense, he diverged from the populist idol who has been a frequent touchstone for Trump: Andrew Jackson, whose portrait hangs in the Oval Office.

"They were absolutely feral enemies," says Fergus Bordewich, author of America's Great Debate: Henry Clay, Stephen A. Douglas, and the Compromise that Preserved the Union. "They absolutely hated each other, they shared almost no views in common."