In West Virginia v. the Environmental Protection Agency (2022), the Supreme Court limited the regulatory authority of administrative agencies. The Court argued that the Constitution required a clear delegation on the part of Congress when an agency was engaged in regulating a “major question.” Critics saw the opinion as a likely challenge to the administrative state, which Justice Neil Gorsuch has been pretty clear about. Defenders saw it as a constitutional restoration of Congressional authority and a much-needed limit on administrative law-making in a constitutional democracy. As such long-standing conservative ideas have begun to triumph on the Supreme Court, including questions about the constitutionality of the modern state that emerged from the New Deal, it is vitally important to understand the constitutional ideas that lie behind these political developments. Johnathan O’Neill’s Conservative Thought and American Constitutionalism Since the New Deal is a timely work that helps shed light on conservative constitutional thinking. Perhaps most importantly, O’Neill’s comprehensive, accessible, and engaging work offers a capacious vision of constitutional thought that extends far beyond a preoccupation with the constitutional jurisprudence of the Supreme Court.

Conservative Thought and American Constitutionalism Since the New Deal is in part an intellectual history of conservative constitutional thought that complements recent scholarship such as Ken Kersch’s (2019) Conservatives and the Constitution. While O’Neill is an historian, and the author of a sharp analysis of originalism that similarly situates it in historical and political terms (Originalism in American Law and Politics, 2005), his approach takes its bearing from American Political Development in reflecting on the relationship between “political order, institutions, and political change” (p. 3). Indeed, he seeks to illuminate how different groups of conservatives sought to meet the challenge of a New Deal order that, in important respects, represented a profound change in American constitutionalism, even while foundational elements of the pre-New Deal constitutional order persisted.

O’Neill’s book offers a richly documented and mostly compelling analysis of the different stands of conservative thought across four broad constitutional areas: the administrative state, federalism, the modern presidency, and modern judicial view. Conceptually, O’Neill groups conservative thinkers as Traditionalists, Libertarians, Straussians, and Neo-Conservatives, letting the diverse group of thinkers and political actors he takes up speak for themselves. While O’Neill is preoccupied by the thinking of these various conservatives, he also gives us a glimpse of the political and institutional changes that were central features of American political development in the wake of the New Deal.

One of the more intriguing features of the book is how it brings out the often-acute tensions and disagreements within conservatism. Indeed, more recement generations of scholars might be surprised to read about Leo Strauss’ student Herbert Storing’s constitutional defense of the administrative state. As Storing argued, drawing on the founding, maintaining “those qualities of the bureaucracy that contribute knowledge and moderation to government and set an example of devotion to the public good is to defend an old position with a new institution” (p. 52). The Neoconservative scholar Edward Banfield similarly noted that “the centralization of authority in the national government had been ongoing and ‘inevitable’ in the United States since the founding” (p. 104). Yet this position has largely been eclipsed in conservative circles by the far more familiar libertarian and originalist critiques of the administrative state. Still, O’Neill’s work also reminds us that the late Justice Scalia was a powerful advocate of deference to administrative agencies, even while those on the Court who view him as a judicial icon to be emulated are much less sympathetic to his longstanding position. And traditionalist conservatives saw the “derailment” of “the original constitutional order” as rooted in Abraham Lincoln’s misinterpretation of equality, which had an open-ended and universal quality that “bore some responsibility for the ‘egalitarianism that characterized the modern, centralized, welfare state’” (p. 30).

The point is that conservatives themselves in the long post-New Deal period argued seriously about ideas and often had divergent understandings of American constitutionalism. The rise of the modern presidency was defended by originalists and Neoconservatives who had sympathy for the notion of a unitary executive, which was frequently linked to a more expensive foreign policy. Traditionalists rejected “an aggressive foreign policy” and the “conception of executive power used to pursue it,” insisting “the founders intended Congress to be the most powerful branch” (pp. 163-64). There were also debates between traditionalists who favored states’ rights and were skeptical of racial equality and West Coast Straussians who insisted on the primacy of natural rights and human equality. While many of these exchanges will be somewhat familiar to scholars, O’Neill’s book will enable historians and political scientists to better understand conservative thought and the growing divisions among conservatives in contemporary politics.

Yet O’Neill eschews writing about the present and avoids the seemingly profound transformation of conservative constitutional thought in recent years. Restoring a proper sense of Congress’s role in the constitutional scheme, against a powerful executive and judiciary, has deep roots in conservative thought. But so, too, does a rejection of racial equality, as does an insistence on ethnic and religious nationalism that rejects not just liberal pluralism but flirts with rejecting liberal constitutionalism altogether. The now fashionable post-liberal strands of conservatism that harken back to Traditionalists are powerfully at odds with the more abstract principles of American constitutionalism articulated by Straussian, Neoconservative, and (some) Libertarian thinkers enamored of Abraham Lincoln. How curiously odd, then, that some West Coast Straussians have taken to sounding like Neo-Confederate Traditionalists, joining the call to overturn the American constitutional order by way of a vague insistence on “regime change.” Curious, too, that some Catholic conservatives are flirting with various forms of theocracy against a tradition of religious liberty, while some culture war conservatives want to use state power to enforce (their) political orthodoxy. This sober book, perhaps prudently, resists weighing in on such issues, even while it will help us better understand them.

Important on its own terms, Conservative Thought and American Constitutionalism Since the New Deal is of heightened interest precisely because it comes at a moment when many of the ideas it engages are triumphing in conservative politics and in the Supreme Court’s jurisprudence. Here I have to say that I found the section on Modern Judicial Power the least compelling section of the book as it was too prone to traffic in notions that the modern Court was a profound break from the past while many of the quarrels over judicial power have been with us from the beginning. This is true, too, of debates about the proper balance between Congress and the executive, just as it is regarding debates about the proper division of state and federal power in the constitutional scheme.

In conclusion, O’Neill insists that constitutional self-government “is tied to the fate of Congress” (p. 298). Calls for Congressional restoration, pervasive among both liberals and conservatives, might point to deeper flaws in our constitutional architecture. The proper balance between American political institutions within a scheme of constitutional self-government has been debated from the beginning. Understanding how to recover that balance might require us to move beyond the past, helpful as O’Neill is in fostering our understanding of it.