Last night, HBO celebrated Veterans Day with The Concert for Valor on the National Mall in Washington, D.C., honoring American vets.

One of the performers invited? Foul-mouthed rapper Eminem.

Well, the results were predictable, as Bill O'Reilly covered in this evening's Tip of the Day.

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"Happy motherf***ing Veterans Day!" Eminem shouted before his performance with Rihanna.

"D.C., make some motherf***ing noise for yourselves, yo!" the 13-time Grammy Award winner added.

O'Reilly said that the concert promoters knew beforehand who Eminem is and what he does, so they insulted all American vets by going ahead with the rapper's vulgar performance.

"There's a quote: If you dine with the devil, bring a long spoon," O'Reilly said. "People rarely change, especially troubled people."

Watch O’Reilly’s Tip of the Day above.

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