I think after OWS, and before that the various "G20" etc anti-globalization protests, it became very clear that the police could effectively contain and suppress mass protest and that it would not be allowed to change anything.

And with better gerrymandering and voter targeting, the votes of protestors could be made irrelevant as well.

(There is a history that needs to be written of how "anti-globalization" moved from a left position to a right one, along the way changing from focusing on goods to focusing on immigrants)