That's not a solvable problem. People are going to try to kill their leaders if they get upset enough. And given how high the stakes are in the modern state which controls every aspect of our lives its going to happen. Whether that's Ortega-Hernandez trying to kill Obama or Hodgkinson trying to kill Republican senators...

The best you can do is try and convince them otherwise, which requires talking to them rather than ejecting them from your community and having them form little communities out of the rejects that then radicalize.