Sen. Elizabeth Warren (D-Mass.) refused to celebrate Columbus Day on Monday, opting instead to observe Indigenous Peoples' Day.

Warren has claimed to have Native American ancestry, something President Trump mocked during a rally in Kansas on Saturday.

Author James Robbins said Monday on Tucker Carlson Tonight that the Massachusetts senator's decision is part of a larger trend in the U.S.

"The trend is to assault the American narrative to make us all feel ashamed to be Americans," Robbins said.

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Robbins said that progressive leaders want people to feel bad about the country's past and thus believe they can rewrite its future.

"If you say that the founders were all evil men, and an evil document and everything in the past was bad, then they can come up with a future that fits whatever they want to make it," he said.

Carlson added that progressives mean to say that Americans don't have the "moral legitimacy" to defend their country.

"It's all about shame," Robbins said. "It's all about blame."

Columbus, Ohio also did not recognize Columbus Day because of budget concerns, and not because of the increasing observance of Indigenous Peoples' Day, according to the mayor's office.

Watch the segment from Tucker Carlson Tonight above.

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