Democrats are rioting and Democrat politicians give them tacit approval because the Democrats have very little political power and they are resorting to violence because they can't gain power through legal means.
The Democrat party has very little power within the Federal Government in Washington D.C. There is a Democrat majority in the House, but Republicans control the Senate and the Presidency and Trump is appointing more and more federal judges who will interpret the law as it was meant when enacted and not according to liberal ideology. And Democrats control fewer state governments than Republicans.
https://www.atr.org/map?amp
Republicans Have Full Control of 22 States, Democrats 15
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Thursday, January 23rd, 2020, 2,00 PM
Republicans have full control of the legislative and executive branch in 22 states.
Democrats have full control of the legislative and executive branch in 15 states.
Population of the 22 fully R-controlled states: 132,338,323
Population of the 15 fully D-controlled states: 120,326,393
Republicans have full control of the legislative branch in 30 states.
Democrats have full control of the legislative branch in 19 states.
Population of the 30 fully R-controlled states: 184,536,246
Population of the 19 fully D-controlled states: 135,248,276