The Republican establishment, which has always distrusted and discounted Donald Trump, is getting increasingly nervous. So nervous, in fact, that some of its media voices are starting to denounce their party’s front-runner in the strongest possible terms. As in, refusing to vote for the man if he’s the nominee. As in, loudly proclaiming that he will destroy the GOP. Viewed from one perspective, this has the smell of panic. Viewed from another, it’s a case of party stalwarts speaking out based on principle.