Echo chamber and confirmation bias, which are connected, are a real problem for interpersonal communication.

Once you lock yourself into a position, you tend to fight to keep it, and most of the time you won't even budge under a rain of reasonable arguments. And the drive for a quick, definite answer is very strong in human beings and very hard to control. It's called cognitive closure.

It seems to happen due to your views being strongly tied to your identity, so every time someone tries to disprove your POV, people feel like someone's attacking them personally and tries to undercut their whole life.

And action usually brings counter reaction, which in the heat of the moment leads to the escalation and often becomes an all out verbal war. People put the armor on, shield themselves and start returning fire until the adversary's dead.

Let's not forget, that at the end of the day we're violent, emotional animals, that view reality mainly as a fight over turf. Be it geographical, be it psychological, be it spiritual.

And we're easily stirred by partisan propaganda, cause that's what mobilises our aggression, our blood lust and leads to events, that everybody knows from the history!