Trump and the people in Trump’s immediate orbit were in direct or very close indirect contact with all of these groups. They knew exactly what was going to happen. In addition to the normal nutty Trump crowds they reached out to these psycho fascist militias and told them to be there to “fight like hell”. People like the Proud Boys know exactly what an invitation and rhetoric like that mean. This was not a rally that got out of hand. This was all planned out and coordinated with other schemes like the false elector scheme and the Georgia phone call. This was deliberate and planned. Trump is an idiot but he knew what he was doing. This has all been documented in the impeachment hearings, the Congressional Jan 6 investigations, and the recent indictments.