For several decades, many (though not all) scholars of U.S. politics have been cognizant of the roles played by religious affiliation and religiosity in motivating political attitudes and behaviors among Americans. Against the backdrop of ever-intensifying political polarization, religion’s relationship to politics would seem to matter more today than ever. That said, perhaps it is the case that the Religious Right’s emergence as a political force has had the unintended effect of diminishing religion’s unique political relevance. Once the Republican Party branded itself as a friend of organized religion (“Faith and the 2016 Campaign,” Pew Research Center, 2016), American political conservatism became less secular almost by necessity. There are stark divisions between conservatives and liberals regarding matters such as whether one must believe in God to be a moral person and the extent to which religion should be separated from government (“Political Typology Reveals Deep Fissures on the Right and Left,” Pew Research Center, 2017). Along with being patriotic and skeptical of Washington, being religious simply is seen as part and parcel of being conservative.

Two new books that rely on historiography help refine and challenge our understanding of the means by which, and the reasons why, religion is so politically salient in the United States. Together, these books offer clues about how religion and polarized politics might continue to affect one another in the future. In his In Rome We Trust, Manlio Graziano focuses on the relatively recent rise of a specific religious group—Catholics—within the ranks of American political elites. In a separate vein, Mark Smith’s Secular Faith challenges the presumption that religion directly shapes American politics. Instead, he argues that religion’s political relevance is a reflection of broader cultural phenomena.

Graziano presents a provocative argument: Contrary to perceptions of decline in Catholicism (among non-Latinx communities), the church today actually is more politically consequential than ever because of the increasing presence of Catholics among the ranks of political elites. The Obama administration included a record number of Catholic officials, notes Graziano, and five of the nine current U.S. Supreme Court justices (Samuel Alito, Anthony Kennedy, John Roberts, Sonia Sotomayor, and Clarence Thomas) are Catholic. Separately, the substantial political clout of the U.S. Conference of Catholic Bishops (USCCB) has grown ever since Vatican II afforded bishops the latitude to speak publicly about politics.

It is empirically true that Catholics are better represented among political elites today than has been the case in previous generations. At least nominally speaking, Catholics are overrepresented in the 115th Congress: 31% of its members are Catholic, compared to just 21% of the U.S. population (Aleksandra Sandstrom, Pew Research Center, Jan. 3, 2017, “Faith on the Hill”). By comparison, only 19% of the 87th Congress was Catholic. Moreover, there are plenty of Catholics to be found on both sides of the political aisle, both at the mass and elite levels, and the USCCB has meaningful access to both Republicans and Democrats because the bishops espouse conservative positions on some issues and progressive positions on others.

Graziano does a fine job of documenting the unlikeliness of these outcomes from a historical standpoint. The church and the United States never have been especially big fans of one another. The history of discrimination against Catholic Americans by the Protestant majority is long and ugly, and for its part, the church has not been fond of Catholicism’s adaptive “Americanization” in the United States, as Graziano points out in Chapter 7. (A critic might charge that Graziano pays too little attention to the significance of Catholic assimilation after the immigrant experience, as well as increasing socioeconomic status over the course of generations, in enabling Catholic Americans to advance into positions of power in government and other social sectors. Nor is the decline in the number of non-Latinx Catholic laity an insignificant matter. Even though more people are entering the Catholic priesthood and other vocations these days (as the author documents), the fact remains that many Catholic laity are leaving the church.

As Graziano emphasizes in his concluding chapter, however, his point is that “the ‘Catholicization’ of the United States is much more significant in terms of quality than quantity, much more so in substance than in form, and much more so in the medium and long terms than in the present” (p. 171). By stepping beyond specific empirics and accounting for broader cultural changes, he sheds light on the basic Madisonian fact that factions need not be large to be influential. A smaller, leaner American Catholic Church need not be a socially weaker one, especially if the clergy and laity who remain are deeply committed adherents. The conservative American Catholic intellectual George Weigel (among other observers) has made precisely this point in a variety of forums (e.g., Weigel, “Catacomb Time?” First Things, http:www.firstthings.com, 26 August 2015).

Meanwhile, in Secular Faith, Smith argues that religion tends not to be a force that proactively changes political and cultural values. Instead, he casts religion as a much more reactive force that adapts to changes in American culture. His historiographical evidence is rooted in explorations of five issues—slavery, divorce, homosexuality, abortion, and women’s rights—with an emphasis on whether and how religion has driven, or been driven by, attitudinal and cultural change in each substantive venue. The evidence is compelling. Smith opens the book with a powerful consideration of how Christians eventually abandoned their opposition to charging interest when lending money. Even though this debate was fraught with conflict (particularly between Christians and Jews) several centuries ago, it is now largely forgotten because Christians accommodated themselves to changing times. Likewise, he argues, religious leaders in the United States more recently have been forced to adapt to changing standards about a range of sociomoral issues. They have three options when doing so: They may 1) insist on being countercultural by holding firm in traditional teachings, 2) draw a bright line between the private and the public, or 3) advocate moving away from traditional teachings, which essentially means changing positions. Smith’s exploration of different religious traditions’ responses to cultural change in the five aforementioned issue areas is engaging and convincing.

The material on slavery and divorce illustrate how thoroughly and quickly organized religion can adapt to cultural change. Over the course of two decades, white religious traditions moved from acceptance (or, at a minimum, acquiescence) to slavery, then to division over its morality, and finally to rejecting the institution entirely (albeit with different levels of enthusiasm at first). Smith acknowledges the important role played by abolitionist religious forces in ending slavery, but he also asserts that cultural forces much broader than organized religion really drove the change. The chapter on divorce supports this argument as well. Consider two basic facts: Secular no-fault divorce laws increased divorce rates, and a majority of Americans are Protestant. Thus, many divorcing American couples in the past half century have been Protestant. To avoid hypocrisy, most religious leaders simply stopped talking about divorce as being sinful. Even the Catholic Church now emphasizes divorce less stridently than was once the case.

The chapters on homosexuality, abortion, and women’s rights obviously deal with issues that remain controversial in twenty-first-century U.S. politics. As public opinion has shifted rapidly in the direction of affirming LGBTQ people, religious traditions that once shied away from even considering the matter of homosexuality are now rapidly changing their positions. Few religious traditions, even in the theologically liberal domain of mainline Protestantism, dared take publicly progressive stands on sexuality at any point in the twentieth century (see Wendy Cadge, “Vital Conflicts: The Mainline Protestant Denominations Debate Homosexuality,” in Robert Wuthnow and John H. Evans, The Quiet Hand of God: Faith-Based Activism and the Public Role of Mainline Protestantism, 2002). Despite the recent turn by many religious leaders (including, to a small degree, Pope Francis) toward open acceptance of LGBTQ people, a sizable minority continue to teach that homosexuality is a sin—and do so more visibly and vocally than before.

While cultural change regarding homosexuality clearly is driving religious accession to policies such as legal same-sex marriage, abortion and women’s rights are issues that have not inspired thoroughgoing cultural change. Smith shows that many religious groups and leaders have correspondingly remained firm in traditional attitudes and teachings about both matters. Those groups and leaders who wish to project a more inclusive approach to abortion and women’s equality have tended not to talk about these issues, rather than taking visibly progressive stands, especially with regard to abortion. The author’s working assumption is that if and when American culture itself becomes more accepting of abortion and more inclined toward viewing women and men as equals, religious institutions will adapt accordingly: “Evolving values and behaviors lead people to update their religious beliefs and identify new political implications flowing from those beliefs” (p. 211).

Despite the obvious differences between these two books, both authors present historiographic analyses that point us toward one conclusion: The political role(s) available to organized religion in the United States (or in any national context) are highly dependent upon the shifting sands of culture. Graziano’s instrumentalist approach shows us that despite plenty of obstacles, Catholic Americans have found their way into positions of political influence, thanks to their patience in waiting for an advantageous zeitgeist, but also because changes in American culture occurred that changed the zeitgeist. Likewise, Smith’s more constructivist approach illuminates the various ways in which religion politically reinvents itself—on an issue-by-issue basis—in reaction to cultural change.

As we move further into the twenty-first century, demographic projections suggest that fewer Americans will identify with organized religion (Robert P. Jones, The End of White Christian America, 2016). If the United States continues to become a more inclusive and diverse society, religious groups and leaders may well react by adopting Smith’s first strategy of adaptation to cultural change, which is to double down on (counterculturally) conservative views. If this is the case, we should expect the religious element of political polarization not to vanish but, rather, to persist as a vocal source of opposition to changes in the status quo.