As I'm sure numerous DU-folk continually point out, Rs are stupid. That was probably the prime narrative during GWB's Presidency, behind Bush lied ... (how some one so stupid could pull off such a subtle "lie", Libs & Progs never explained). So the Rs could not possibly be behind the BLM thugs* disrupting Bern-Ins.
It's much simpler and closer to Libs' & Progs' homes. The BLM thugs* are going after the Ds (rather than the Rs, for now) because blacks have faithfully voted for the Party of the KKK for decades, and the BLM thugs* think blacks have gotten nothing (= not enough free @#$%) for their votes. I also think the reason the BLM thugs* are going after Bernie is Clinton Cash.
* For what little it should be worth, I have no hesitation to use "thug" when "white" people act thuggishly.