Between blue states and red states, it is easy to discern America’s geographic political polarization. Republicans move to reliably red states such as Texas, Florida, and Wyoming, while Democrats migrate similarly toward states such as Massachusetts, Minnesota, and Oregon. Subtler is the intrafamily polarization characteristic of today’s politics.

For its own part, geographic polarization is well documented. The New York Times reported an analysis of post-2020 presidential election voter registration records that demonstrates public intuition for the trend. Democratic voters tended to move to towns President Joe Biden had won while Republicans went for towns former President Donald Trump had won — each group by the same 19 percentage point margin.