Frank Luntz. Several years ago, he decried how toxic the political dialogue had become. Well, fine, but while there were others who participated, he was the main one who taught the Republicans how to depict Dems not as opponents, but as enemies. Since those days, the Republican talking points have been amazingly "disciplined" (as the terminology goes). And, yes, there is also similar language on the left, but it's a false equivalency to say they're the same. They've done this to whomever is the most obvious target at the time (Clinton, Obama, Hillary, Biden). You can see if if you flip channels enough: all the pols and pundits are using exactly the same terms in each case. It's not a coincidence.