Donald Trump went on CNN this afternoon to do what has become his specialty of late: make a complete fool of himself. His appearance was precipitated by every sensible person on both sides of the aisle wondering why, exactly, Mitt Romney voluntarily chooses to associate with Trump, given the real estate mogul's vocal obsession with birtherism and his many years as the cartoonish avatar of repellant avarice.

So there he was, in the Situation Room, getting manhandled by Wolf Blitzer on President Obama's place of birth -- an issue that never actually was an issue and was unmercifully put to rest by the president himself when he released his long-form birth certificate. The highlight of the interview? After Trump questioned the birth certificate's authenticity, the presence of Obama's mother at the hospital, and the birth announcements in the Honolulu papers, Blitzer responded with admirable restraint: “Donald, you're beginning to sound a little ridiculous, I have to tell you.”

The new fuel for Trump's birther fire is the Breitbart.com “exclusive” about Obama's publisher wrongly claiming 20 years ago that he was born in Kenya -- the same “exclusive” that the Breitbart people said had nothing to do with birtherism. During an interview with CNBC earlier today, Trump referred to the Breitbart story, claiming that Obama told his publisher that he was “born in Kenya and raised in Indonesia.” He brought it up again in his CNN interview: “Obama hates the subject. When his publisher comes out with a statement from him made in the 1990s that he was born in Kenya and that he was raised in Indonesia, and all of the sudden it comes out, I think it's something that he doesn't like at all.”

That's factually incorrect; the statement was not from Obama but was rather a “fact-checking error” by the literary agency, which told Political Wire: “There was never any information given to us by Obama in any of his correspondence or other communications suggesting in any way that he was born in Kenya and not Hawaii.”

Regardless, it's become the new shiny object for the incurable birther remnant. Who could have predicted?