Carl von Clausewitz’s well-traveled assertion that war is the continuation of policy, or politics, by other means remains enormously popular; so much so, in fact, that scholars have repeatedly chosen to emphasize it as the most important part of his legacy.[i] But they ought to have known better. That assertion is no more representative of the sum of his thinking than the phrase “will to power” signifies the totality of the thought of the German philosopher Friedrich Nietzsche. The folly of reducing the thoughts of any great thinker to a single phrase is well known, though some Cold War-era Clausewitz scholars had good reasons for doing so. From the standpoint of his influence and legacy, however, privileging one dimension of war over others merely distorts the value of his three-dimensional model of armed conflict, his “wondrous trinity,” and all but mutes his emphasis on critical inquiry. To preserve both the intricate and analytical aspects of his model, we ought to elevate Clausewitz’s “supreme question,” his imperative concerning the importance of understanding the type of war at hand according to its circumstances, to a more prominent place in his legacy.
The Supreme Question
To be sure, Clausewitz’s contributions to military theory also include such concepts as friction, center of gravity, and the defense as the stronger form of war. Nonetheless, as important as these concepts are, they pale in comparison to his warning to heads of state and military commanders that they must “recognize the kind of war they are undertaking, neither mistaking it for, nor attempting to turn it into something it cannot be because of the nature of the circumstances.” He regarded this task, furthermore, as “the first, the supreme, the most decisive act of judgment” policymakers and military strategists must make.[ii]
And for good reason; failing to understand the type of war one is about to embark upon makes it almost impossible to craft an appropriate strategy beforehand, save by accident. At a minimum, that failure can cause one to pay a higher price than necessary for victory; in extreme cases, it can lead to catastrophic defeat. This question is also central to the strategic direction of military actions during a conflict, the active component of strategy.
As is well known, Clausewitz’s approach to theory hinged on critical analysis: the purpose of theory was to explain rather than to predict. In fact, the supreme question, critical inquiry, and the trinitarian model of war’s nature go hand in hand in determining the type of war one is about to undertake. For, however one reads the trinity—whether as its primary elements of hostility, chance, and purpose, or in terms of its secondary elements, the populace, the military, and the government—its crucial point is that a uni-dimensional or a bi-dimensional understanding of war is inadequate. Like “three codes of law,” each dimension must be obeyed; each must be given its analytical due.[iii]
Unfortunately, answering the supreme question is simple in concept but difficult in practice. It can involve inflexible or simplistic categories of war, for instance, as well as lead to a counterproductive clash of opposing views of war’s nature or character. The example of US strategic thought during the Vietnam era (discussed below) illustrates both problems. While answering the supreme question is difficult, that fact only serves to underscore its importance; like any useful skill, it must be exercised.
Categorizing the Vietnam Conflict
American strategic thinkers recognized four types of war by the early 1960s: total or all-out war, general war, limited war, revolutionary war. The first meant a war in which at least one party uses all means at its disposal including nuclear weapons to “destroy” its opponent. The second referred to a war similar in nature to total war, but which did not involve nuclear weapons. Limited war entailed fighting for restricted objectives, with only a portion of one’s resources, and within a geographically circumscribed area. Revolutionary war was defined as a conflict in which a nongovernmental and a governmental party attempted to destroy each other.[iv] As Samuel Huntington and others noted at the time, these broad categories were considered mutually exclusive in theory, though the boundaries between them were not precise. Beneath this typology, one also finds a lesser category called “forms of warfare.” This category describes different species of military activity involving specific military forces, weapons, and tactics. Guerrilla warfare, naval blockades, and aerial bombardments were considered forms of warfare.[v]
Unfortunately, the mutually exclusive nature of these four categories, along with the vagueness of their boundaries, created confusion for US strategists. More precisely, it enabled America’s strategists to see what they wanted to see in the entry into, and conduct of, the conflict in Vietnam. Indeed, the type of war Hanoi was waging essentially spanned all four types, including all-out war in the sense that the major parties acted as if nuclear weapons might be used, even though they never were. US Army Colonel Harry Summers, for instance, would later argue the Vietnam conflict was not a revolutionary war, but a general conflict mistakenly fought as a limited war. He saw only the first Indochina War (1945-1954) was a revolutionary war; the second conflict (1959-1975) he regarded as a war of conquest in which Hanoi attempted to dominate all Indochina. He regarded Viet Cong activities as nothing more than a “simulated insurgency,” a strategic distraction, that drew attention away from Hanoi’s main effort, the operations of the North Vietnamese Army (NVA).[vi] He was hardly alone in these beliefs. On the other hand, the CIA’s Major General Edward Lansdale saw the conflict as a revolutionary struggle, or people’s war, almost from the outset.[vii] His views were seconded by several others, including former foreign service officers, such as Douglas Pike, and military analysts such as George Tanham and John J. McCuen.[viii]
Still others, such as Bernard Brodie, Robert Osgood, Thomas Schelling, and Henry Kissinger, saw the conflict as a limited one that had to be waged as the war in Korea had been fought—with self-imposed constraints. They held this view even though few of the preconditions necessary for conducting a limited war, as laid out in Osgood’s seminal work, Limited War, existed with respect to Vietnam.[ix] In fact, Osgood outlined three “conditions” and three “rules”: (a) the fighting should involve only a small number of major participants, preferably two; (b) hostilities should be contained geographically, and operations should be restricted to military targets only; (c) the conflict should require minimal commitment of each belligerent’s resources so as not to disrupt their economic, political, and social activities; (d) the political objectives must be restricted and clearly communicated to friends and foes alike; (e) open communications must be maintained to enable negotiations to commence as early as possible; and (f) the physical dimensions of the conflict must be restricted insofar as doing so accords with the political objectives.[x] Of these, only (d), (e) and (f) obtained in Vietnam, and only inconsistently.
Nevertheless, US Secretary of Defense Robert McNamara and later US National Security Advisor Kissinger, both mindful of the real and obvious need to avoid unwanted escalation, attempted to turn America’s involvement in Vietnam into the type of war they believed it had to be—a limited conflict—rather than as the synthetic war it was. US strategists missed the fact that the Vietnam War was not one particular type, but rather a synthetic combination of all categories (save all-out war involving nuclear weapons, though the threat of escalation on the part of Beijing and Moscow was present). Whereas US strategic thinkers were constrained in their thinking by the categories of conflict they had established, and by debating which one the Vietnam War fit into, Hanoi had managed, perhaps unintentionally, to achieve some strategic synergies by fighting a series of general, revolutionary, and limited campaigns.[xi] The lesson here is one should not allow oneself to be held captive by one’s categories and should, instead, assess a conflict according to its circumstances. It is well known Clausewitz eschewed rigid categories, though it is impossible to avoid some form of classification.
Debating the Nature of the Vietnam Conflict
Confusion over the type of war the United States faced in Vietnam also revealed a fundamental disagreement over the general nature of the conflict. As Summers openly admitted, “Almost a decade after our involvement, the true nature of the Vietnam war is still in question.”[xii] In fact, two principal paradigms of war’s nature underpinned American strategic thinking at the time—traditional and political—and these were at odds with one another.[xiii] The first saw war’s nature as an extension of human nature, and it favored prosecuting a conflict with the Jominian core principles of concentration, offensive action, and decision by battle foremost in mind. The second paradigm saw war’s nature in mechanistic terms. It believed a single, ill-considered action could trigger runaway escalation, not unlike the violent uncoiling of a tightly wound spring. This paradigm upheld political purpose as the alpha and omega of armed conflict, and as the only meaningful element in the Clausewitzian trinity. It essentially embraced the “great dictum,” presumed policy was intelligent, if not rational, and ascribed to it the role of controlling the military’s core principles, which it likened to instincts, and the public’s passions, which it considered irrational. Accordingly, it endeavored to direct violence in a precise and incremental manner to avoid provoking an escalatory response from Moscow or Beijing.
After the war, as the number of analyses of public support for the conflict increased, the traditional paradigm expanded but did not “shift” in the Kuhnian sense of the term.[xiv] It continued to regard armed conflict as a violent extension of human nature, but it increasingly associated that nature with social groups: societies behaved as individuals but on a larger scale.[xv] As a result of this revision, however, the social dimension of armed conflict rose to the same level of importance as its military and political dimensions. In short, the revised traditional paradigm anticipated, by some thirty years, what British General Sir Rupert Smith astutely observed regarding the ubiquity of modern war’s social dimension, namely, that armed conflict now takes place “amongst the people,” in environments marked by constant confrontation, and the chief role of military force is to create conditions conducive to convincing rather than killing.[xvi]
Nor did the political paradigm undergo a Kuhnian shift. On the contrary, it became more convinced of its appropriateness and thus more resistant to revision. It transferred blame for the failure of the US intervention in Vietnam to the American populace, claiming the public lacked the culture necessary to support a limited war, a culture it needed and ought to have if its government were to retain its position as a leader of the free world. Put differently, this paradigm faulted the public for failing to appreciate Clausewitz’s dictum that war was merely the continuation of policy, or politics, by other means. Ironically, if indeed the public lacked the will to surrender its blood and treasure to a vaguely defined and poorly conceived limited war, then US grand strategy ought to have developed a different course of action, one that could have succeeded despite that particular circumstance. An example of just such a course of action would have been to draw the line of Containment elsewhere—not in Indochina—to encompass only those allies and strategic partners along the Pacific rim that mattered. Defending South Korea, Japan, Formosa, the Philippines, Australia, and New Zealand, with Singapore, Malaya, and Indonesia as potential trade-space, would have been easier to accomplish and to sell. In other words, if the Domino theory was the excuse for intervention, then draw the line where the dominoes are more capable of withstanding the threat. Instead, US strategists attempted to walk the tightrope between doing what was necessary to maintain public support for the intervention in Vietnam and not doing so much as to arouse hawkish passions. But both the White House and the Pentagon proved incapable of walking that line.
It would be an error to conclude the United States lost the war in Vietnam because its leading strategic thinkers failed to appreciate the importance of Clausewitz’s supreme question, though most of them claimed to have read On War so ought to have been familiar with the question. There were many reasons for the failure of America’s intervention in Vietnam. But answering the supreme question performs a valuable service by requiring strategists to confront a host of crucial questions, which will in turn expose risky assumptions and unwarranted expectations.
Clausewitz’s supreme question reflects a three-dimensional model of armed conflict that goes beyond the two-dimensional framework (political and military) that still dominates much of US strategic thinking in the twenty-first century. One may debate whether it ought to be enlarged to include economic or technological elements, thereby squaring the trinity or converting it into a pentagram. Regardless, when US strategic theorists have managed to move beyond their prevailing framework—and have done so without denigrating the crucial role of political influence—the greater potential of Clausewitz’s legacy will have been realized.
To be sure, a legacy is both more and less than the body of works an individual has left behind. It consists, unavoidably, of only those gems scholars selected from a possible trove of jewels. For too long, those researchers who searched among Clausewitz’s works have found and admired the same gems. As a result, familiar nostrums about the relationship between war and policy have been persistently and reflexively repeated. We now have an opportunity to prevent that verse of history from repeating itself.
[i] Michael Howard referred to it as Clausewitz's “famous dictum,” in “British Grand Strategy in World War I,” Grand Strategies in War and Peace, ed. Paul Kennedy (New Haven, CT: Yale University, 1991), 31; Bernard Brodie called it the Prussian's “great dictum,” in his “Guide to the Reading of On War,” in C.v. Clausewitz, On War, trans. and ed. Michael Howard and Peter Paret (Princeton: Princeton University, 1976), 645; Raymond Aron labeled it Clausewitz's “famous formula,” in Peace and War: A Theory of International Relations (New Brunswick, NJ: Transaction Books, 1966), 23. See also Eliot A. Cohen, Supreme Command (New York: Anchor, 2003), 7-8.
[ii] C.v. Clausewitz, Vom Kriege, 19th Ed. (Bonn: Dűmmlers, 1980), 212; On War, 88.
[iii] Vom Kriege, 213; On War, 89.
[iv] Samuel P. Huntington, “Guerrilla Warfare in Theory and Policy,” in Franklin Mark Osanka, ed., Modern Guerrilla Warfare: Fighting Communist Guerrilla Movements (New York: Free Press of Glencoe, 1962), xv-xxii; Richard H. Sanger, “The Age of Sociopolitical Change,” Naval War College Review 22, 2 (Oct. 1969), 16. US military doctrine carried similar definitions.
[v] Huntington, “Guerrilla Warfare,” xvi.
[vi] Harry G. Summers, On Strategy: A Critical Analysis of the Vietnam War (Novato: Presidio, 1982), 84-85, 90.
[vii] Edward G. Lansdale, “Viet Nam: Do We Understand Revolution?” Foreign Affairs 43, 1 (Oct. 1964): 75-86.
[viii] Douglas Pike, Viet Cong: The Organization of the National Liberation Front of South Vietnam (Cambridge: MIT, 1966); and War, Peace, and the Viet Cong (Cambridge: MIT, 1969). George K. Tanham, Communist Revolutionary Warfare: From the Vietminh to the Viet Cong, 2d. ed. (New York: Praeger, 1967). Lt. Col. John J. McCuen, The Art of Counter-Revolutionary War: The Strategy of Counter-insurgency (London: Farber, 1966).
[ix] Robert E. Osgood, Limited War: The Challenge to American Strategy (Chicago: University of Chicago, 1957).
[x] Osgood, Limited War, 24.
[xi] Lien-Hang T. Nguyen, Hanoi’s War: An International History of the War for Peace in Vietnam (Charlotte: University of North Carolina, 2016).
[xii] Summers, On Strategy, 83.
[xiii] For further details, see Antulio J. Echevarria II, War’s Logic: Strategic Thought and the American Way of War (Cambridge: Cambridge University, 2021, forthcoming).
[xiv] Thomas S. Kuhn, The Structure of Scientific Revolutions (Chicago: University of Chicago, 1970).
[xv] Consider: Herman Kahn and Anthony Wiener, eds., American Values: Past and Future, vol. I, Values, Attitudes, and Life-Styles in a Changing World (Croton-on-Hudson: Hudson Institute, Dec. 31, 1974); Henry E. Eccles, Military Power in a Free Society (Newport RI: Naval War College, 1979).
[xvi] Gen. Rupert Smith, The Utility of Force: The Art of War in the Modern World (London: Allen Lane, 2005).