Tucker Carlson debated former Obama aide Austan Goolsbee over illegal immigration and the rise of automation in the workplace.

Carlson told Goolsbee, now an economics professor in Illinois, that there is no reason to allow an influx of illegal immigrants who are low-skilled workers, especially when middle-class jobs are at risk in coming years.

Goolsbee said that technology both destroys and creates new jobs. Carlson asked whether he would be happy with "replacing all economics professors with AI" in that regard.

"When the number of jobs goes down, immigrants leave," Goolsbee said as the discussion shifted to illegal immigration.

Carlson asked why Democrats would offer "free health care, housing vouchers and free food" to illegal immigrants instead of helping American citizens.

When Goolsbee doubted the veracity of the remark, Carlson asked if he heard that New York Mayor Bill de Blasio is offering free health care to illegal immigrants and all New Yorkers.

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Goolsbee said that the fertility rate of the "native-born population is not enough to sustain" current population numbers in the United States.

Carlson asked why the government couldn't instead encourage Americans to have more children.

"How grotesque is that?" he asked. "It's actually disgusting you just said that. Why not help your own people to have more children? Why is the answer to import more children."

Goolsbee said the government's actions to date have not worked in that regard, citing the child tax credit.

Watch more above.

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