How cooperation, love, compersion, and unity are just the other side of the coin of competition, hate, epicaricacy, and destruction.
We are hard-wired for "us-them" dichotomies. We form "us-them" judgments in seconds, but race isn't the only factor - symbolism like team hats can be more powerful in calculating "us-them" relationships. The good news is we can use symbols to unite. The bad news is we can also use symbols to divide. Oxytocin exaggerates cooperation within the in-group, but enhances viciousness towards the out-group.
https://youtu.be/lrzXE5XttOE