Tucker Carlson says he’s not a white supremacist but John Oliver isn’t buying it.

On Sunday’s “Last Week Tonight” the host tackled the Fox News host’s frequently troubling rhetoric on matters of race and ethnic diversity.

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On his own show, Carlson asked someone to “tell us in very clear language what a white supremacist is.”

To help Carlson out, Oliver used his own words against him, playing a clip in which he accused U.S. Rep. Ilhan Omar of “hating America,” adding, “We have every right to fight to preserve our nation and our heritage and our culture.”

“Wow, ‘preserve our heritage and culture’ — that is direct,” Oliver responded. “In fact, his prewritten caption there, ‘We have to fight to preserve our nation and heritage,’ drew a lot of comparisons to the ‘Fourteen Words,’ the famous white supremacist slogan that says, ‘We must secure the existence of our people and a future for white children.’ And when you put the two together there is, you know, a slight similarity there.”

Oliver added that Carlson “is smart enough not to openly say into a camera that certain races are more deserving of scorn or less worthy of respect, he will just heavily imply that depending on who he’s talking about.”

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He continued, “That is the whole thing with Tucker. He might not say Black or white, he’ll insist that he’s for ‘colourblindness.’ He’ll build in deniability by phrasing things like a question like, ‘What does racism look like?’ while kind of embodying the answer. But when you put all of this together, the pattern is clear. He is scared of a country that looks nothing like the one he grew up in because diversity isn’t our strength, immigrants make our country poorer, dirtier, and more divided, and any attempt to change that culture is an attack on Western civilization.”

Finally, Oliver said, “All of which is really just a long way of saying that when Tucker says, ‘What is white supremacy?’ the answer is, ‘Basically, that.’ It’s a belief that in a country where white people are dominant, that’s all down to their natural and innate abilities, and any effort to change that is an affront to the natural order of things.”