It's strange because we also have an extreme culture of litigation, and so much as an unwelcome or aggressive touch (without injury) could technically support a civil lawsuit or criminal charges for assault/battery.

The difference is that we apply justice differently depending on your political belief, so the acceptable violence is usually one-directional. Any violence by left protestors will be treated akin to terrorism. If you're a right wing crazy harassing people protesting for a left cause, police will look the other way and you may not even be convicted for murder (e.g., Rittenhouse). Worse, the police are usually the ones being irrationally violent - like the George Floyd protests in which nonviolent civil protest was suppressed with military-level equipment, tactics and violence.