Let me begin with a confession: I am guilty of the sin of linguistic imprecision, using the du jour phrases of our culture war without considering my words in their full context. In particular, both secularism and, even more so, Christian nationalism, require tremendous care, whether in a casual or polemical argument. It may even be, as Hillsdale history professor Miles Smith IV writes in his new book Religion & Republic, that the latter term “has become essentially meaningless,” more of a Rorschach test than a well-defined ideology.

Which brings me to my review of Smith’s book. Without hyperbole, I believe he has written an incredibly important work of history. Indeed, I think this book will prove to be absolutely essential amid ongoing attempts to speak intelligently about the role of Christianity in America.

To be clear, this is a work of history. While Smith occasionally comments on contemporary discourse and, in his conclusion, points toward possible applications of his argument, his primary purpose is to explore the relationship between religion and public life in the United States before the Civil War.

Smith’s critical contribution is to eschew the rhetorical extremes of the left and right that recast late 18th century America as either embodying rigid church-state separation or as a purer, more sacral time in our erstwhile Christian republic. Smith characterizes the early United States as “a republic of Christians committed to what I have termed ‘Christian institutionalism.’” Christians “wanted to maintain Christian precepts in their nation’s various social and political institutions without sacralizing those principles or subordinating the American republic to a church.”

Phrased in negative terms, Smith proposes “that the United States Constitution’s disestablishment did not secularize society, nor did it remove institutional Christianity from the civic, state educational, or political spheres.” It also “did not create a unitary social or semi-sacralized Christian nation as some conservative evangelicals and neo-theocrats argue.” The “religious order” enacted by the Constitution “was liberal in its views on establishmentarianism and at the same time conservative on its conceptualization of Christianity’s place in the civil and social orders and in its intellectual influences.”

There was a widespread view in the early republic among Christians (and the few non-Christians) that church and state, even with disestablishment, retained “their mutual purpose of creating and upholding a moral order committed to historically Christian conceptions of virtue.” The notion of a strict wall of separation between church and state, moreover, finds little currency in the views of the authors of the Constitution. Congress, for example, used public funds to pay for Congressional chaplains and reauthorized the Northwest Ordinance, which went so far as to declare religion “necessary to good government and the happiness of mankind.”

Transcending notions of state churches and establishment, Smith writes that “Christians remained committed to upholding Christian institutions in the civil, political, and social structures of the American republic,” in order to sustain America as a Christian nation. This institutionalism can be seen across numerous spheres of the early republic.

Legislatively, states passed laws and retained constitutional provisions that confirmed themselves “as the chief arbiters of morality and religious law in the United States.” For example, Vermont, in a model that would be copied or expanded upon elsewhere, enacted a law in 1797 that forced Sabbath observance by disallowing business and other activities on the basis that the Sabbath is “in the highest degree, promotive of the peace, happiness, and prosperity of the people.”

Similarly, US courts “continued to be deeply influenced by Christian, and more specifically Protestant, understandings of civil law.” Joseph Story, who served as an Associate Justice of the Supreme Court for over three decades, wrote explicitly that Christianity was part of the Common Law of England, which formed the legal heritage of the United States. The First Amendment prevented “any national ecclesiastical establishment,” Story wrote, and “cut off the means of religious persecution.” Yet, as Smith summarizes, while the First Amendment mitigated persecution, “Early Republic judges and officers of the law did not believe that mitigation of persecution led to political and social libertinism regarding religion.”

Smith highlights other areas where Christian institutionalism can be seen in the early republic. He notes that the federal government “went to great lengths to support and protect missionaries, and to use missionaries to further the political and social aims of the political American republic.” In the realm of education, Protestant ministers “regularly headed and staffed” state colleges, and these institutions “had explicitly Christian commitments worked into their curricula.”

I wrote earlier that Smith’s book is timely for contemporary debates over religion and public life in the United States. Toward the end of the book, Smith starts to draw out contemporary applications of his argument. He cites early 20th-century Presbyterian luminary J. Gresham Machen, arguing that “Machen and other Protestants in the United States rightly understood that they did not need a churchly or sacralized or even Christian state to maintain Christian institutions in the American republic, even as they knew the American populace ignored the Christian foundations of American social and civil life at their own peril.”

Smith also rejects reactionary notions that Protestants can suddenly turn back the clock to the early republic, but argues they can “engage their neighbors by being healthy and responsible stewards of healthy and responsible Christian institutions at the local, municipal, and state levels, and in the arts and sciences as well as in politics.” Between the individual and the nation lies a set of “intermediate institutions–civil, political, and religious” that warrant serious care and attention.

Indeed, while primarily making a historical argument, Smith has laid the foundations for further conversation about what Christian institutionalism could mean for American Christians engaged with society, politics, and culture. Between the Scylla of a totally sacralized state and the Charybdis of total separation between church and state, Smith has found a narrow but vital channel.