Humans do care about large groups, in the form of nationalism, or their religious or ideological equivalents. Those groups can be very large.

Unfortunately, those almost by definition involve opposition to some other group. It's not just the politicians who see the conflict more in terms of winning over their opposition. The politicians do it because it's popular with their supporters.

Actual advances are hard. Defeating the opposition is much easier, and often more satisfying because it pays off today.

You won't fix that by fixing the politicians, who are just responding to what the people demand. Any politician you convince will be defeated by the next demagogue. Getting the people to stop enjoying the polarization so much seems more doable, if only because they're right around you. You can see them on HN every day.

Whether they can be convinced... honestly, I doubt it. But I think that for those optimists who believe that something can be done, I think they should consider looking around them rather than away to distant politicians and other shadowy figures. The real causes are right here.

I personally consider that much scarier.