You've drastically altered the reality of US history. Violence and guns were a huge part of it. Labor unions had actual shoot outs with union busting officers, Malcolm X was absolutely using guns (King also had them), some draft protests were intentionally violent. If you really look, almost every "peaceful" movement had violent parts or another similar movement that was violent.

Perhaps the greatest example is the race riots, specifically LA where the police completely abandoned areas and local shop keepers used their own weapons to protect their livelihood.

Furthermore, the right to bear arms is heavily limited, automatic weapons have been banned for around 50 years at this point, getting any gun is subject to background checks in basically every case, age limits are also in place, "dangerous" things like suppressors require additional fees and paperwork in order to own.