Sarah Burns, an associate professor of political science at the Rochester Institute of Technology and a former student at the Claremont Graduate University, is not the first to point out that our current system of separation of powers is warped from its founding design. She comes at this issue from a distinctive and interesting angle, however, and supports it through an informative discussion of how war powers have been understood and contested across American history. Her new book, The Politics of War Powers, part of the venerable American Political Thought series at the University Press of Kansas, makes a valuable contribution both to our understanding of the ideas that shaped the founding and to the ongoing debate about the imperial presidency and perversion of the war powers.

The book adopts a distinctive theoretical perspective on both the presidency and the founding that helps distinguish it from the many books on presidential war powers. It puts Baron de Montesquieu front and center in considering founding era thought. It is a familiar fact that Montesquieu, or the “celebrated Montesquieu” as Alexander Hamilton refers to him in the Federalist Papers, was among the most influential writers in the Federalist camp who embarked on federal constitutional reform in the United States in the 1780s. Donald Lutz found that Montesquieu was the most widely cited political writer in the newspapers and pamphlets published in the United States in the last decades of the eighteenth century, and particularly so in the 1780s when the Constitution was under consideration. John Locke was frequently discussed in the 1760s as Americans began to contemplate independence, but his star fell after the Revolution. Blackstone surged to prominence in the 1790s when the new federal government was being established and administered, but it was Montesquieu who provided the political maxims and analytical tools to help the Americans think about how to design a constitution to govern a free republic. Moreover, Montesquieu’s ideas informed both the Federalists and the anti-Federalists. He was the intellectual common ground on which debates about the Constitution were conducted. Anti-Federalist critics of the Constitution frequently complained that the document was not sufficiently faithful to Montesquieu’s dictum that the legislative, executive and judicial powers must be kept strictly separated. The Federalists in turn insisted that the proposed constitution could be reconciled with Montesquieu, though it might allow for more sharing of powers than many of the state constitutions did. Montesquieu was the unassailable starting point for constitutional design, though there was disagreement about the implications of his theory. This is not to say that a Lockean spirit did not permeate the American early republic, but it was the Spirit of the Laws that sat at the elbow of competing writers on American constitutionalism.

Remembering Montesquieu

It has been easy to overestimate Locke and underestimate Montesquieu when thinking about the Constitution. Locke was unquestionably important to the launch of the American project and his ideas permeate the Declaration of Independence and Revolutionary era polemics. Locke’s work is central to the liberal political tradition, influential to both subsequent American political discourse and the study of political philosophy. Locke’s work has an appealing systematic quality that draws in the modern political theorist and facilitates deductive arguments about political rights and duties. Locke himself was embedded in the polemical literature surrounding the great English debates that elevated Parliament and limited the powers of the British crown, setting the stage for the creation of a republican form of government in America.

Montesquieu, by contrast, is a more difficult political thinker to pin down. The Frenchman is unquestionably an important theorist of the Enlightenment and in the history of political philosophy, but, like Tocqueville, Montesquieu’s work does not fit neatly within a particular political tradition and his writing is more complex and nuanced than pure philosophy. Again like Tocqueville, Montesquieu’s writing has a sociological quality that gives it a rich empirical grounding but that loses the clarity of the more abstract and deductive approach of writers like Locke. His insights are nuanced and buried in a morass of details.

Montesquieu is, however, the most obvious political thinker for understanding the separation of powers. Locke was important to elevating Parliament in its constitutional disputes with the English king, but his thinking about the ongoing balance between an executive and legislature was quite rudimentary. It was Montesquieu who grasped that the English political order was creating a system of constitutional checks and balances with separated institutions performing distinctive functions side-by-side within the government. It was Montesquieu who imagined how an executive and a legislature could productively divide and share powers within a republican government, and it was Montesquieu who conceptualized the judiciary as an independent third branch of government and not just an extension of the executive. It is thus natural that American constitutional debates would have prioritized Montesquieu and his omnipresent warning that “when the legislative and executive powers are united in the same person, or in the same body of magistrates, there can be no liberty.”

Burns appropriately puts Montesquieu at the center of her analysis of founding era thought on the scope of presidential authority generally and particularly in relation to the war power. She does not shy away from the subtlety of Montesquieu’s thought and gives an extended effort to trying to lay bare the pragmatic advice that Montesquieu has to offer to statesmen. A repeated theme is Montesquieu’s emphasis on the need for a “moderate constitutional order” and the significance of a “delicate” and “complex” political system for creating and maintaining this moderation. That delicate arrangement is easily subverted, either by external or internal forces. The American constitutional order is sometimes characterized as a mechanical clockwork, with carefully balanced gears designed to keep the constitutional order on a fixed path. Montesquieu is skeptical that such plans can survive the encounter with reality. Despite the frequent emphasis by the founders on his maxims about separation of powers and the like, Montesquieu in general did not offer a blueprint for a well-designed constitutional order. Every situation was different, and events were fluid. A statesmen must know how to adjust to the needs–and wishes and capacity–of his people.

All this is a bit vague, and it unfortunately is not greatly clarified as the book moves through its historical chapters. Montesquieu offers wisdom and caution, but the theoretical discussion leaves us balancing multiple goals and concerns and understanding that we need to find, and maintain, balance. What exactly we should be attempting to balance and how we should do it are less clear. There are few bright lines that can help us identify when our delicate balance is becoming unbalanced, when our moderate constitutional order is succumbing to the extremes, when we are no longer doing a good job of assessing and responding to the situation as we find it. Burns shows us what Montesquieu had to say about such disparate regimes as ancient Rome and eighteenth-century France and England, but that often highlights how deeply contextual Montesquieu’s analysis and advice often is. Like Edmund Burke, Montesquieu could be a prudent statesman, but generalizations are hard to come by. Even so, Burns’ perspective is a valuable one and one that has not received enough attention in recent American constitutional theory that has tended to find its inspiration in other sources. Montesquieu might be a bit sphinxlike, but that is not to say he is mistaken.

Debating Presidential War Powers

The bulk of the book examines the history of debates over presidential war powers in American politics. Many books of this type limit their focus to the twentieth century. Such a focus, of course, is not unreasonable given the dramatic expansion of presidential war powers over the last hundred years and the rise of the United States to superpower status with troops and security commitments spread across the globe. The dominant scholarship nonetheless leaves out some important debates and historical developments, and it leaves the impression that, in Montesquieu’s terms, the delicate balance of the American constitutional order was fine until something began to go wrong in the twentieth century.

Burns’ history shows that the scope of presidential authority over the military and American security has always been a problem. To be sure, the situation has become more challenging for our inherited constitutional order in more recent decades, but the source of those challenges has been implicit in the constitutional design all along. Montesquieu’s emphasis on vigilance against the possibility of a well-established moderate constitutional order becoming unbalanced over time as it encounters new situations is well-taken. Burns also helps us understand the ways that this order strains to contain the ambitions of political leaders. 

The book’s historical chapters nicely combine political behavior and ideas. Burns takes up individual episodes of warmaking, or threatened warmaking, to see how our institutions have responded. These brief histories are informative, but the real contribution is the sensitivity to the debates that surrounded those episodes. She unpacks constitutional debates in a broad sense. Burns is less interested in the narrowly legalistic arguments that sometimes occupy Congress and the Office of Legal Counsel than the broadly constitutional arguments that emerge from political debates over how America should be governed. She focuses on the respective responsibilities of different institutions for securing the national well-being and traces how they make important decisions about when and how to go to war. Such debates–and the worry that the president might consolidate too much authority over war–have occupied us since the founding. Burns is as illuminating in discussing the Mexican-American War as the Cold War or the War on Terror. The early debates are notable for the appreciation, including by presidents, of the importance of preserving constitutional forms. 

Part of what has changed in more recent decades is the expanding indifference to, and perhaps fatalism about, the problem of balance. As the geostrategic ambitions of the United States extended beyond the Western Hemisphere, a powerful and largely autonomous president capable of initiating and managing foreign policy seemed increasingly indispensable. We are half a century removed from Arthur M. Schlesinger, Jr.’s jeremiad against “the imperial presidency,” and yet the president seems no less imperial today than it did at the end of the Vietnam War. Despite the occasional complaints of current legislators like Rand Paul, Mike Lee, and Justin Amash, Congress as a body has shown little interest in seriously revisiting the authorization for the use of force that launched the War on Terror two decades ago. Attempting to rebalance the relationship between Congress and the president seems beyond our capacity.

Early in the book, Burns notes, “as the founders knew, in a good constitutional order, the government has to have the ability to respond to emergencies without warping its own institutions to address them.” This is a challenge that the founders understood, but it is also a challenge that Montesquieu took seriously. As Burns details, Montesquieu knew that a successful state must be capable of providing security to its people. What that requires is a moving target. The security threats faced by the nation now are different than the ones faced by earlier generations of American leaders, and a moderate constitutional order must be adaptable to those changing needs without losing the kinds of checks and balances that keep a nation from veering off course or sacrificing the liberty and well-being of the people to the ambitions and glory-seeking of its leaders. Burns might not be able to provide easy answers to the problems that bedevil our polity, but she has insights to offer that are worthy of reflection in the years ahead.