Radio host David Webb and Fox News contributor Jessica Tarlov debated the civility of President Trump versus his liberal critics.

Tarlov said Trump crossed a line by suggesting that Rep. Maxine Waters (D-Calif.) has a third-grade IQ, when he called her a "low-IQ individual" and guessed that her intelligence quotient ranked in the mid-60s.

Several black female leaders also wrote to party leadership, ripping them for failing to defend Waters against previous Trump critiques.

"His attacks are definitely uncivil," Tarlov said on "Outnumbered," calling for Democrats to defend Waters against the insults.

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Webb said Trump's IQ comment was "a joke" and that "liberals think they own laughter."

"Liberals seem to think we need to care about everything you find wrong," Webb said, adding that the left "is ginning up violence" on a recurring basis.

He pointed to the attempted assassination of Republican lawmakers on a Virginia baseball field last summer, Waters calling for the harassment of White House officials and Press Secretary Sarah Sanders being driven from a Virginia restaurant.

Webb added that he needs formal Fox News security when he covers National Action Network rallies and other events headlined by liberals.

Watch the debate above.

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