Former Education Secretary Bill Bennett said Sunday on Fox & Friends that President Trump's stance on enforcing the U.S. border could make a "real and profound difference" on the nation's drug epidemic.

Bennett, who served as President George H.W. Bush's "drug czar," said that a border wall was the principle promise of Trump's 2016 presidential campaign.

"He's making a line in the sand now and I think he's absolutely right," he said of Trump.

He added that opposition to the president's desired border wall is "ridiculous," and that those who are against it simply want to oppose Trump.

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Bennett also said that Trump has "very, very good" instincts when it comes to the flow of drugs entering the U.S. from Mexico.

By weight, 86 percent of heroin that entered the United States in 2016 was of Mexican origin, according statistics from the Drug Enforcement Administration.

"After 9/11 we shut down the border. When we shut down the border, drugs didn't come in," Bennett said. "If you shut down that border, if you close it off, if you build a wall, it can have a real and profound difference."

Watch more from "Fox & Friends" above.

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