The trends that brought us this situation have been in existence for decades, but 2015 may be remembered as the year when we broke apart, and political differences became primary cultural signifiers. Disagreements about ideological principles, or even policy preferences, seem to be taking a back seat to identity politics. It doesn’t matter what you believe in so much as what grouping you belong to, and how willing you are to fight for the sliver of America you represent. 2015 was the year of tribalism. Our politics are less high-minded than ever.

If tribes strike you as primitive, it’s not just you. Tribes tend to assign leadership, not based on experience or wisdom, but based on strength. Much of what we are witnessing today is very base (no pun intended) and essentially comes down to machismo: The other guys are out to get us so we need our toughest guy to get them first. This is the major rationale for Trump supporters, who see him as an “alpha” in a sea of wishy-washy Beltway insiders.

Conservatives once hated identity politics and victimhood—but then again, we once supported free trade, too. Perhaps our disdain for tribalism was always a high-minded, yet doomed, effort to suppress the natural, carnal state of a fallen humanity. You and I may view politics as being about ideas and human flourishing, but a lot of people believe it’s really about power—about making sure scarce resources are allocated to “our” people.