The New York Times reports that Rush Limbaugh and company have decided to turn the label "fake news" against the mainstream media:

Until now, that term had been widely understood to refer to fabricated news accounts that are meant to spread virally online. But conservative cable and radio personalities, top Republicans and even Mr. Trump himself, incredulous about suggestions that fake stories may have helped swing the election, have appropriated the term and turned it against any news they see as hostile to their agenda.

This may be effective, but it's not particularly clever. It's just an old Soviet trick--still used in contemporary Russia, as Konstantin Sonin and I recently described. When Russian media say that U.S. elections are "rigged," the goal is to debase the term so that allegations of (real) election rigging in Russia seem unexceptional. Similarly, when professional propagandists in the U.S. claim that mainstream media are peddling "fake news," the aim is not to discredit CNN and the New York Times--that was done years ago--but to convince listeners that any claim of "fake news" is partisan.

Is there a how-to manual that all propagandists read, or does any reasonably competent practitioner just figure out what works through trial and error?