Former President Bill Clinton. (Matt Rourke/Associated Press)
Opinion writer

Filmmaker Joel Gilbert, the conspiracy theorist who believes President Obama has a secret Muslim prayer inscribed on his wedding ring, made a splash in 2012 when he said Obama had plastic surgery to conceal that his real father was labor activist Frank Marshall Davis, who raised his son to lead a communist revolution.

Four years later, and just in time for Election Day, Gilbert is back with a new film alleging that Bill Clinton has a 30-year-old son he sired with a black prostitute. And on Tuesday, Gilbert hauled the young man to Washington and gave him a speech to read to the TV cameras at the National Press Club.

“As you can see I’m the black son of former president Bill Clinton and the stepson of Hillary Clinton,” the young man, Danney Williams, read as Gilbert, off to the side, mouthed many of the words.

Actually, you could only see him as Clinton’s son if you imagined Clinton six inches shorter, with a different build and different facial features. But no matter.

“At this time I am reaching out to Miss Lewinsky, Monica Lewinsky,” Williams went on, looking to Gilbert for instruction and holding up a letter. “I’m asking that Miss Lewinsky allow me to borrow her blue dress in order to obtain a DNA sample of my father’s, former president Bill Clinton, in order to finally prove that he is my father.”

Nannygate, Travelgate, Whitewater, Filegate: it's tough to remember all the scandals that plagued then-President Bill and Hillary Clinton through the '90s. For millennials --- here's what you missed. For everyone else, here's a refresher. (Sarah Parnass,Adriana Usero/The Washington Post)

In fact, Williams’s DNA was tested, 17 years ago, when his mother sold it and her story to a tabloid, which compared the boy’s genetic material to Clinton’s DNA markers and concluded Clinton wasn’t his father.

That essentially ended the intrigue — until late last year, when longtime Donald Trump adviser Roger Stone declared: “I will get justice for Danney Williams — stay tuned.” The Trump confidant had decided the original DNA work was wrong, and he teamed up to make that case with conspiracy-minded radio host Alex Jones, an avid Trump backer who lent his InfoWars news outlet to the cause.

Gilbert, who was hired by Stone’s pro-Trump super PAC to design a “Super Trump” billboard for Times Square in September, made a film about Williams. The pro-Trump outlet Breitbart News, whose former chief Stephen Bannon now runs Trump’s campaign, and the Drudge Report began to trumpet the long-debunked love-child story. Gilbert is a fixture on InfoWars, which live-streamed Tuesday’s event.

If past is prologue, Trump will, in this final week of the campaign, find a way to mention the story of Bill Clinton’s love child. Stone to Jones to Bannon to Trump: This is how Trump legitimizes the fringe. There’s nothing furtive about this vast, right-wing conspiracy: Trump relies on the private advice of Stone, Jones and Bannon, and he has made their conspiracy theories mainstream.

As the website Right Wing Watch has documented, Jones has boasted that he gives Trump off-air advice, and he took credit for Trump voicing the theory that Ted Cruz’s father was involved in John F. Kennedy’s assassination. He has been pleased to see Trump repeating him “word-for-word” on the campaign trail. Trump, who has hailed Jones’s “amazing” reputation, has parroted claims made by Jones (and often by Stone) that American Muslims celebrated the 9/11 attacks, that the election is “rigged” against Trump, that Antonin Scalia was murdered, that Hillary Clinton used drugs before a debate and, of course, that Obama’s birth certificate was fake.

Most ominously, Trump has echoed the “globalist” conspiracy theories embraced by Stone, Jones and Bannon, full of anti-Semitic tropes. In October, Trump blamed a “global power structure” for wrecking the economy and said Clinton “meets in secret with international banks to plot the destruction of U.S. sovereignty.”

Now comes the Bill Clinton love-child conspiracy, even if it collides with another popular conspiracy theory: that Chelsea Clinton wasn’t fathered by Bill Clinton because he’s sterile.

Williams seems unclear on his motives. He said Tuesday that he was seeking the former president’s DNA because “I want to know my dad.” But moments later he was calling Clinton a “deadbeat” and a “big felon.” Williams wants to raise $100,000 for his campaign but said he had only $2,800; Gilbert booked the room and said he funded the film.

Gilbert quickly lost control of the event. One woman declared she was going to baptize Williams and then, failing to find oil in her handbag, performed the ritual with bottled water. There were prayers and laying on of hands and shouts from the participants that the press is “racist” and “bought off.” Conservative activist Cliff Kincaid told the gathering I was there “to write a story making fun of” Williams.

But I wouldn’t make fun of Williams. The ones worthy of ridicule are the powerful and unscrupulous men exploiting him.

Twitter: @Milbank

Read more from Dana Milbank’s archive, follow him on Twitter or subscribe to his updates on Facebook.