Jesus Salvador places crosses in a pauper's cemetery where hundreds of unidentified migrants are buried Tuesday, Feb. 14, 2017, in Holtville, Calif. Photo Credit: GREGORY BULL / AP

An anthropologist who’s studied life and death on the U.S.-Mexico border says the fight over the wall distracts from a much more difficult conversation that Americans don’t want to have.

Jason De León, a professor at the University of Michigan who runs the Undocumented Migration Project, delivered the Robert G. Bone Distinguished Lecture on Wednesday at Illinois State University. He grew up on the border and has applied his anthropological expertise to better understand how migrants die as they enter the U.S.

De Leon said the fight over President Donald Trump’s demand for the border wall—he was rebuffed by Congress and now plans to do it using a national emergency declaration—baffles him.

“I feel like we’ve taken a step back 40 years in this current political moment,” he said. “The Trump era has reminded us that there’s a big segment of the American population that has literally no idea what’s going on at the U.S.-Mexico border or the history of our immigration policies.”

Instead of a wall, U.S. leaders should be focusing on why migrants are coming here and how much the U.S. economy relies on them to do the jobs Americans won’t, De Leon said.

“You don’t need $5 billion to build a wall. If you truly believe that (illegal immigration needs to stop), police the workforce,” De Leon said. “We love migrants when they’re working here in the shadows. It seems we hate them at the border.”