I'm entering a restaurant while other customers are leaving. There is a bottleneck at the door. If I see the passerby is a stereotype of my political opponents, I rush through first and do not hold the door open for them. If I see the passerby is a stereotype of my political allies, I smile, nod, and hold the door open for them.

This sort of friction exists in every single interpersonal medium because politics distorts the cooperative game, and turns society into a backstabbing match. There's no point in tracking intermediary steps towards inevitable political violence, you'd be better off just studying combat tactics.