In a recent post, I discussed some reasons why political polarization has become much worse in recent years.  In the comment section, I was startled to see people deny that polarization had actually become much worse.  (Perhaps some commenters are too young to recall the 20th century.)  In any case, a recent article in The Economist provides some data:

Scholars of American politics are particularly dismayed by rising levels of “affective polarisation,” the political science term for the hostility one person feels towards members of the other party relative to the feelings they have towards members of their own party. Levels of affective polarisation have risen more than two-fold since the 1970s when the American National Election Studies, a quadrennial academic survey started at the University of Michigan, began asking citizens to rate how they felt about members of either major party. In 1978, according to the survey, the difference between Americans’ ratings of members of their own and ratings of members of the other party on a 100-point “feeling thermometer” scale was 27 points. The gap had widened to 56 by 2020.

Yes, political polarization is real and getting much worse.