The history of 'outside agitators' — from Gaza protests to Martin Luther King Jr.

The term "outside agitator" has staying power.It's been used against protestors throughout history, from the Civil Rights Movement, to the anti-Vietnam War protests and now during the pro-Palestinian demonstrations on college campuses."Outside agitator" was also used to describe some of the people who protested the killing of Michael Brown in Ferguson, Missouri In 2014.Who exactly are the "outside agitators" and what purpose does it serve to call them out? For sponsor-free episodes of Consider This, sign up for Consider This+ via Apple Podcasts or at plus.npr.org.Email us at considerthis@npr.org.