Just south of the national Mall, the U.S. Holocaust Memorial Museum stands as a grim reminder of what the Nazis did.

Directly across the Mall from the museum, white nationalists were shouting Nazi slogans Saturday in a meeting at the Ronald Reagan Building.

They shouted “heil” and called the media “lügenpresse” just as the Nazis did, and leader Richard Spencer quoted Nazi propaganda in the original German.

The same sort of propaganda that’s exhibited as a memorial to humanity’s worst conduct on one side of the Mall is held up as a model for celebration on the other. The museum said in a statement Monday that it’s “deeply alarmed.”

“[Spencer] said that America belongs to white people. His statement that white people face a choice of ‘conquer or die’ closely echoes Adolf Hitler’s view of Jews and that history is a racial struggle for survival,” the museum said. Then it offered a history lesson to anyone who has forgotten: “The Holocaust did not begin with killing; it began with words.”

Those words eventually led the Nazi party, which came into power legitimately in Germany, to kill 6 million Jews and millions more Communists, Gypsies, Poles, gay people and people with disabilities.

Jewish organizations have been divided in their response to Donald Trump’s white nationalist supporters, who call themselves the alt-right — in particular, to Trump’s decision to appoint Stephen Bannon, the head of the alt-right’s most prominent website, as one of his top advisers. Some have demanded that Trump drop Bannon and denounce his racist supporters, while others have stayed quiet for the time being in the hope of developing a working relationship with the new administration.

But on the subject of racial hatred, the Holocaust Museum argued Monday, there should be no disagreement. It asked all leaders, political and religious, to denounce hatred in America. Anyone who wants to see where the worst hatred can lead can walk half a mile from the Reagan Building to the museum.

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