I'm afraid I missed the conference of white supremacists in Washington this past weekend.
I was hosting my daughter's bat mitzvah.
But I have a pretty good picture of what happened, because luckily — for me, if not for them — several other journalists attended Saturday's gathering of alt-right leader Richard Spencer's National Policy Institute at the Ronald Reagan federal building.
Attendees shouted "heil" and "Lugenpresse," a Nazi term that means "lying press." Some of the few hundred attendees applauded mention of the Daily Stormer, a neo-Nazi website. Reality TV personality Tila Tequila tweeted an image of herself and others giving a Nazi salute and the misspelled words "Seig heil!"
White nationalists and counter-demonstrators clashed violently in the street outside the gathering in downtown Washington, and, as The Washington Post's John Woodrow Cox reported, inside and outside a family restaurant, Maggiano's, in northwest Washington.
The scenes seemed as if from another time and another place, but in Donald Trump's America, they are here and now. And if Trump doesn't do something more forceful to disown his neo-Nazi hangers on, they will continue their brazen march into the mainstream.
The New York Times quoted Spencer at the conference saying that "we have a psychic connection, or you can say a deeper connection, with Donald Trump in a way that we simply do not have with most Republicans."
"We've crossed the Rubicon in terms of recognition," Spencer said, arguing that "America was, until this last generation, a white country designed for ourselves and our posterity. It is our creation, it is our inheritance, and it belongs to us."
Shortly after the election, Trump said his supporters who were harassing Muslims and Latinos should "stop it."
But they aren't stopping. In the past few days, a city park in Brooklyn was defaced with swastikas and the message "Go Trump!" while an Arab American Uber driver in Queens filmed another driver shouting at him: "Trump is president so you can kiss your [expletive] visa goodbye, scumbag. … They'll deport you soon."
While the white nationalists were meeting in Washington and clashing with protesters, Trump was engaged in a Twitter fight with the cast of the Broadway musical "Hamilton." Trump demanded the actors apologize for urging Vice President-elect Mike Pence, who attended the show, "to uphold our American values and to work on behalf of all of us."
Rather than quarrel with that unobjectionable message, perhaps Trump could listen to the George Washington character in "Hamilton" sing "One Last Time":
"Like the scripture says:
Everyone shall sit under their own vine and fig tree
And no one shall make them afraid."
This passage, from Micah 4:4, is in Washington's letter to the Jews of Newport, Rhode Island, in 1790. The rabbi recalled these words during my daughter's bat mitzvah this weekend.
"Happily," Washington wrote, "the government of the United States, which gives to bigotry no sanction, to persecution no assistance, requires only that they who live under its protection should demean themselves as good citizens, in giving it on all occasions their effectual support."
Continued the first president: "May the children of the stock of Abraham who dwell in this land continue to merit and enjoy the good will of the other inhabitants — while every one shall sit in safety under his own vine and fig tree and there shall be none to make him afraid."
Please read Washington's words, Mr. President-elect, and repeat them to Richard Spencer and his ilk as you brush off the white nationalists riding on your coattails.
There is room for cooperation on much of Trump's agenda. But cooperation is difficult, if not impossible, when a president gives sanction to bigotry.
Follow Dana Milbank on Twitter, @Milbank.