Establishmentarians have antidisestablishmentarians in every institution and all walks of life.
This news Madison Police, Fire Fighters & Teachers Threaten Local Businesses with Boycots reveals that they are moving into full reactionary mode against any of us who wish to see our now dysfunctional institutions reformed. As RB says, "the letter is not yet authenticated," so be cautious. Still, given the videos of thuggish behavior appearing daily, and the ever more brazen behavior of the Left tallied at this blog over the years, it's likely to be authentic.
Beware and prepare.