A sure-fire way of assessing the threat that leftists feel toward any challenge to their nonsensical narratives and preposterous policies is to measure the long knives and "important" people they drag out to slam the competition.
Whether it's the leftwing JournoList cabal of 400 so-called journalists and academics who in 2007 colluded to launch relentless character assassinations against every person who challenged Barack Obama about anything, or the obsessive sexist attacks and slander leveled in 2008 against Republican VP candidate Sarah Palin, or, more dramatically, the strange death of Obama critic Andrew Breitbart, the bleeding-heart left has zero tolerance for opposing opinions and those who express them.