“empirical research has come out persuasively showing that riots in the past have not generally swung public opinion toward the causes they’re rooted in. Particularly with the 1960s riots, the evidence suggests that white voters’ negative reactions to these uprisings in black communities fueled the rise of “tough on crime” politicians whose policies perpetuated some of the problems that protesters in the ’60s stood against and that demonstrators today are now protesting.
We don’t know if this research on the 1960s uprisings can be perfectly generalized to protests today, when the circumstances, political climate, and population are different. There are other studies suggesting that, at least in limited circumstances, riots have helped some causes.
But there are concerning signs about the way today’s protests are going. With violence becoming a bigger and bigger part of the news, figures like President Donald Trump can ignore the overall message and cause of the protests and instead focus on calling for “law and order” and the deployment of the National Guard. Some, like Sen. Tom Cotton (R-AR), have called for military deployment in cities hit by riots. Unrest at protests is producing the very attitudes and positions — from “tough on crime” to the literal militarization of policing — that protesters are standing against.”
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“research from the past suggests the path to meaningful change, particularly for racial justice, is typically more successful through peaceful means.”
https://www.vox.com/2020/6/2/21275901/police-violence-riots-george-floyd-minneapolis