Except when they really believe this, and find out it's not true, whether it's traveling the Middle East or Africa, or just going down the wrong alley in any number of American cities. We can be that, and we should be that, but that is potential, and must be learned. Human beings at our root are savage tribal predators, weak individually, but stronger than any other land animal in groups. Our behavioral elasticity has allowed us to rise above that, while still serving those needs of the brain, and with the right cultural backgrounds (Western civilization's roots in Mesopotamia, and whatever some of the East Asians got right and spread, that I am historically more ignorant of), create great civilizations, and go above and beyond those basic instinctual needs. Look at South Africa, right now, turning itself into Zimbabwe 2.0, for example: that is humanity getting back to its root. To prevent that requires each generation to be raised with values beyond oneself, beyond near-term needs, and with skepticism/vigilance of oneself and one's community.