Buckley. Disappointing. He would have looked much better if he calmly explained that Vidal- calling him a Nazi was a case of projection.
Buckley sued Vidal....and later dropped the suit.
http://www.nytimes.com/books/98/03/01/home/vidal-suit.html
Vidal called Buckley a “pro-crypto-Nazi,” a modest slip of the tongue, he later said, because he was searching for the word “fascist” and it just didn’t come out. Inflamed by the word “Nazi” and the whole tenor of the discussion, Buckley snapped back: “Now listen, you queer,” he said, “stop calling me a crypto-Nazi or I’ll sock you in you goddamn face and you’ll stay plastered.” Smith attempted to calm the exchange with “gentlemen, let’s not call names,” but the damage had been done. The two men, considerably subdued, met the following night for the last of their week of debates.
By early 1969, Vidal said he had put the incident behind him. But Buckley had not, and so he proposed to the editors of Esquire that he write a piece about his exchanges with Vidal. Naturally, seeking fair play, the magazine asked Vidal if he would like to write about Buckley, and it was agreed that the pieces would run in consecutive issues - Buckley’s in August 1969, Vidal’s in September. The requisite lawsuits ensued at the time, and Vidal, who made it clear to Buckley that he would not back down, won something of a pyrrhic victory: Buckley, told by a judge that he probably would not win if his suit went to court, agreed to let Esquire pay his legal fees and issue an apology, after which he dropped his lawsuit. Vidal’s legal fees went unreimbursed.