Sen. J.D. Vance (R-OH) revealed Tuesday night a secret best kept from his running mate, former President Donald Trump, a political analyst argued Wednesday. Vance’s performance at the CBS News debate against Gov. Tim Walz (D-MN) subtly exposed the Ohio senator’s limits in loyalty to the Republican presidential nominee, according to the Atlantic columnist Helen Lewis. “It became clear that the outwardly subservient Vance is already plotting his post-Trump future,” Lewis wrote. “Don’t tell the mad old king, but his most loyal baron is looking at the crown and wondering how well it would fit his …