One of the most striking and consequential shifts in U.S. society over the last five decades is the increasing share of Americans who have abandoned religion. In 1972, just 5% of Americans reported that they had no religious affiliation, according to the General Social Survey. In 2021, that number had skyrocketed to nearly 30%. In 2020, the number of Americans who never attend religious services reached 75 million, while the number who attended weekly was 65 million, according to the Cooperative Election Study.

Being economically and educationally stratified means that houses of worship are becoming more politically homogeneous as well. If someone walked into an average Protestant or Catholic church in the 1980s, they were just as likely to sit next to a Democrat as a Republican. That’s no longer the case: In almost all majority-white Protestant churches, political conservatives dramatically outnumber those who are left of center. In 1978, 50% of white weekly churchgoers were Democrats and 40% were Republicans. Today, 60% identify as Republicans and just 25% as Democrats.

When religion becomes so politically uniform, it can have corrosive effects on democracy. The conservatism of white Christian churches has helped to lead tens of millions of liberal Americans to leave religion behind entirely and join the ever-increasing ranks of the non-religious. In 2021, 51% of people who identified as politically liberal said that they had no religious affiliation, compared with just 12% of people who identified as conservative.

In general, Americans are becoming less tolerant of people who are different from us.

Houses of worship would thus be ideal spaces for social contacts to flourish. If churches, synagogues and mosques were once again full of people from across the economic and political spectrum, it would help build bridges not just in the congregation but in the larger community.

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