With one declaration, President Donald Trump upended an aspect of our immigration system.

Last week, Trump announced that the US would begin imposing a $100,000 fee for all new H-1B visa applications — that is, the visa that high-skill foreign professionals use to work in the US. By hiking the fee to such an exorbitant sum, Trump hopes to compel companies to turn to high-skill American workers instead – not to mention bring in revenue.

“We’re going to take that money and we’re going to reduce taxes, we’re going to reduce debt,” he said. Workers in tech, finance, medicine, and science make up the majority of the 85,000 people awarded H-1B visas each year.

It’s the latest plank in the administration’s restrictive immigration policy, one that the administration argues will benefit Americans.

But Britta Glennon, an economist at the Wharton School at the University of Pennsylvania, sees it differently. “We actually have a lot of evidence showing the positive benefits that H-1B workers and skilled immigrants more generally have brought to the US,” Glennon told the Today, Explained podcast. She worries that Trump’s new policy will erode America’s innovative capacity and dim its future prospects.

Below is an excerpt of Glennon’s conversation with host Sean Rameswaram, edited for length and clarity. There’s much more in the full podcast, so listen to Today, Explained wherever you get podcasts, including Apple Podcasts, Pandora, and Spotify.

President Trump........

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