“Partisan polarization remains the dominant, seemingly unalterable condition of American politics,” Pew Research declared in November 2021, a year after a presidential election that drew the most voters in American history (partisanship and polarization, it turns out, increase participation). “Republicans and Democrats agree on very little — and when they do, it often is in the shared belief that they have little in common.”If anything, this holds even truer today.
…Scholars in the field of politics and heritability are generally in agreement about the partial heritability of political ideology.
In the specific case of the United States, Christopher Dawes and Aaron C. Weinschenk, political scientists at N.Y.U. and the University of Wisconsin-Green Bay, write in their paper “On the genetic basis of political orientation,” “Twin studies show that political ideology is about 40 percent heritable.”
In separate work examining “the liberal-conservative ideological spectrum in world terms, communism to fascism not Democrats and Republicans,” Rose McDermott, a professor of international relations at Brown, found that “about 60 percent of overall liberal-conservative ideology is genetically influenced.”