Antifa and their violent thug allies like those in BLM are the Democrat party's street-level shock troops. Democrat mayors across America have told their police departments to not interfere with Antifa's political violence. They are used to keep the Democrats' political opponents off the streets, silent and out of view of swing voters. It's not much different from how the Democrats used the KKK to beat down blacks who were voting Republican back in the Democrats' heydey.