ADVANCING 

STRATEGIC THOUGHT 

SERIES

THUCYDIDES

WAS RIGHT:

DEFINING 

THE FUTURE 

THREAT

Colin S. Gray

Carlisle Barracks, PA and

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Strategic Studies Institute

and

U.S. Army War College Press

THUCYDIDES WAS RIGHT: 

DEFINING THE FUTURE THREAT

Colin S. Gray

April 2015

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ISBN 1-58487-670-0
v

FOREWORD

To define future threat is, in a sense, an impossible 

task, yet it is one that must be done. In this monograph, Dr. Colin S. Gray explains that the only sources 

of empirical evidence accessible to us are the past and 

the present. We cannot obtain understanding about 

the future from the future.

Dr. Gray draws noticeably upon the understanding of strategic history obtainable from Thucydides’ 

great History of the Peloponnesian War. The monograph 

advises prudence as the operating light for American 

definition of future threat, and the author believes 

that there are historical parallels between the time of 

Thucydides and our own that can help us avoid much 

peril. The future must always be unpredictable to us 

in any detail, but the many and potent continuities in 

history’s great stream of time can serve to alert us to 

what may well happen in kind.

The Strategic Studies Institute is pleased to offer 

this monograph to assist policymakers and strategic 

thinkers in understanding this vital topic.

 

 DOUGLAS C. LOVELACE, JR.

 Director

 Strategic Studies Institute and

 U.S. Army War College Press

vii

ABOUT THE AUTHOR

COLIN S. GRAY is Professor of International Politics 

and Strategic Studies at the University of Reading, 

England. He worked at the International Institute for 

Strategic Studies in London, UK, and at the Hudson 

Institute in Croton-on-Hudson, NY, before founding 

the National Institute for Public Policy, a defense-oriented think tank in the Washington, DC, area. Dr. Gray 

served for 5 years in the Ronald Reagan administration on the President’s General Advisory Committee 

on Arms Control and Disarmament. A dual citizen of 

the United States and UK, he has served as an adviser 

to both the U.S. and British governments. His government work has included studies of nuclear strategy, 

arms control, maritime strategy, space strategy, and 

special forces. Dr. Gray has written 27 books, including: The Sheriff: America’s Defense of the New World 

Order (University Press of Kentucky, 2004); Another 

Bloody Century: Future Warfare (Weidenfeld and Nicolson, 2005); Strategy and History: Essays on Theory and 

Practice (Routledge, 2006); Fighting Talk: Forty Maxims 

on War, Peace and Strategy (Potomac Books, 2009); National Security Dilemmas: Challenges and Opportunities

(Potomac Books, 2009); The Strategy Bridge: Theory for 

Practice (Oxford University Press, 2010); War, Peace 

and International Relations: An Introduction to Strategic 

History, 2nd Ed. (Routledge, 2011); Airpower for Strategic Effect (Air University Press, 2012); Perspectives on 

Strategy (Oxford University Press [OUP] 2013), which 

is the follow-on to Strategy Bridge. The final volume in 

the Strategy Bridge trilogy, entitled Strategy and Defence 

Planning: Meeting the Challenge of Uncertainty, was 

published by OUP in 2014. Dr. Gray is a graduate of 

the Universities of Manchester and Oxford.

ix

SUMMARY

This monograph examines the challenge in future 

threat definition. In order to do so, it is necessary to 

understand where identification of threat originates, 

and how and why such identification is made in the 

context of international political relations. This analysis makes fairly heavy use of the ideas in Thucydides’ 

great History of the Peloponnesian War. Effort is expended here to explain why a work written in Greece, in 

the late-5th century B.C., has high value for us today 

as a vital aid to understanding of our own current, 

and indeed future, security context.

The monograph offers conclusions/recommendations in four broad clusters. First, prudence is recommended as the guiding light in the face of an irreducible 

ignorance about the future. Second, the monograph 

explains that there is considerable real (political and 

cultural) discretion about the particular identification and definition of threat. Third, the analysis flatly 

rejects the idea of historical analogy as a vital source 

of evidence on future threat; instead, the concept of 

the historical parallel, the difference between the two 

ideas, is very large. Fourth, although the contemporary United States is indeed unique and exceptional 

as an actor on the world state, it is nonetheless simply 

a very large and powerful state that is obliged to behave according to the same rule book, and plan with 

a familiar playbook, as have other great powers of the 

past and present. 

1

THUCYDIDES WAS RIGHT: 

DEFINING THE FUTURE THREAT

The fact that, historically speaking, correct threat perception is exceptional—resting perhaps on luck or 

intuitive judgement, that is, on unreliable resources—

stands in sharp contrast to the common assumption 

that threat perception is easy.

 Klaus Knorr, 19761 

Yet the only empirical data we have about how 

people conduct war and behave under its stresses is 

our experience with it in the past, however much we 

have to make adjustments for subsequent changes in 

conditions.

 Bernard Brodie, 19762

WHAT IS THE PROBLEM?

The subject that lies unavoidably at the core of this 

analysis is the challenge of understanding both what 

Americans will, or certainly should, understand about 

threat in the future and what kinds of policy and strategy actions might be implied as appropriate. Unfortunately, elements key to this inquiry are far from being 

all but self-explanatory, even when or if the familiarity of popular concepts appears to attribute a quite undeserved merit to them. By way of firing two “shots 

across the bow” of this subject and accepting the risk 

of my appearing unduly negative, it is necessary to 

decline to be unduly impressed by the two highly potent ideas that must drive this study—threat and the 

future. The sheer familiarity of these concepts can paralyze our critical capacity. I should hasten to explain 

that the high purpose here does not lie in the explora-
2

tion of interesting ideas in a quest after understanding 

for its own sake. Rather, this inquiry is motivated and 

organized with the intention of discovering a way, 

or ways, in which the United States, and particularly 

its Army, could act in order to counter the problems 

that attend and infest the concepts of the future and of 

threat. The fundamental subject is the challenge to the 

United States that inalienably is issued by the need to 

be able to cope well enough with what may come to be 

regarded in the future as threats.

Notwithstanding the uncontentious linked dual 

concepts of threat and the future, it is necessary to 

recognize that both concepts are characterized by immense contemporary lack of knowledge on our part. 

The beginning of wisdom has to be frank recognition 

of our total ignorance about detail of and from the future. This is an obvious and unarguable truth that carries profound meaning for politics and strategy, but 

all too rarely is properly understood. In fact, so truly 

resistant are people to the full meaning of the “future” 

that often they succumb to the temptation in effect 

to deny temporal actuality. The somewhat awkward 

truths are that we can obtain no information about 

the future from the future, and indeed that the future 

never arrives.3 Officials and scholars do not challenge 

this law of physics, but they are prone to forget it, or 

at least to behave in their endeavors in planning as if 

it were only a matter of minor inconvenience. In the 

analysis and discussion here, I attempt to address the 

awesomely challenging problem of how the United 

States and its Army can be ready enough to cope adequately with the difficulty of not knowing for certain 

what it may be required to do, or against whom it may 

have to be prepared to do it. It is necessary to begin by 

acknowledging that any, and indeed every, explana-
3

tion of future threat has to be able to refer to a body 

of evidence in its regard. What unlocks somewhat the 

mystery of future threat can only live in the evidence 

we have more or less accessible to us, indirectly, in the 

record of strategic history, past and present.

We are used to employing the apparently opposed, 

though actually complementary, ideas of continuity 

and change. To enrich greatly this dynamic duo, we 

need also to contextualize treatment of future threat 

by adopting the master notion of the great stream of 

time.4 This imperially inclusive organizing concept 

requires us to accept as legitimate the idea that strategic history is unending, just as it had no confidently 

identifiable beginning. What the concept of the stream 

of time can do for us is provide all important temporal 

context. While on the one hand, it accommodates considerable change in the character of strategic affairs, 

on the other, it insists upon our appreciation of the 

many, indeed fundamental, continuities in our history. On grasping the meaning of the concept of the 

great stream of time, scholars, soldiers, and politicians 

should feel rather less lonely and perhaps afraid in 

their unavoidable ignorance of the future.

There can be no hiding from a fundamental problem that must drive this discussion; specifically, how 

can we prepare for our future security when, all too 

literally, we neither have, nor are able to obtain, a 

thoroughly reliable understanding of our society’s 

security needs in the future? Restated in short form, 

how do we go about our defense planning when we 

cannot know what perils the future will bring? It is 

appropriate, if more than a little worrisome, to recognize as reality the enduring contextual truth that defense planning must and will be done, no matter the 

state of our grasp of current, let alone future, dangers.5
4

Bearing in mind the certain fact that our future strategic history can be played out only once regardless of 

the imaginative alternatives that futurists can devise, 

it should be clearly understood that history, in common with strategy, is all about consequences that will 

not usually be easy to understand with well-founded 

confidence.

Thus far I have chosen to emphasize the scale and 

the quality of the problem that must confront defense 

planners. The basic reason for such negativity does not 

lie in deep-seated pessimism on this analyst’s part, but 

rather in a determination to insist upon full realization 

of the nature of the challenge to policy and therefore 

to our strategy. How can we “define the future threat” 

when that future is a book closed to us forever? It is 

ironic that, although we are, and will remain, entirely 

ignorant of the future in detail, by contrast with that 

bleak ignorance we can, and should, be thoroughly 

knowledgeable about the context of threat in our society’s future. How and why is this remarkable contrast 

possible? My citation of Thucydides’ great History of 

the Peloponnesian War, when considered in tandem 

with the concept of an unending great stream of time, 

can provide the basis for an adequate answer.6 The 

particular merit for this analysis in Thucydides’ history has been well-flagged by many scholars, as well 

as political and military professionals.7 However, the 

core of the lasting value in the Athenian general author’s literary historical work has been well expressed 

succinctly by Robert Gilpin. This American professor 

has claimed that “The classic history of Thucydides is 

as meaningful a guide to the behavior of states today 

[1981] as when it was written in the fifth century B.C.”8
5

Gilpin also offers the following thought that many 

of our contemporary scholars most probably would 

deem close to absurd, were they ever prepared to 

consider it seriously.

But, in honesty, one must inquire whether or not 

twentieth-century students of international relations 

know anything that Thucydides and his fifth-century 

compatriots did not know about the behavior of states. 

What advice could today’s students give that would 

have enabled the Greeks to have prevented the great 

war that destroyed their civilization?9

We know for certain that Thucydides believed that 

his then contemporary history of the great war that 

all but destroyed Greek civilization was, in effect, the 

story of the persisting, indeed permanent, history of 

mankind. If we find this belief plausible, at the very 

least, then it means that we have valuable, if admittedly variable, access to an abundance of evidence 

with high educational merit for our defense planners 

today. We do not and cannot know the strategic future 

in detail, but we should have more or less available to 

us the understanding of what was probably considered and actually attempted, over the course of 2 1/2 

millennia of global strategic history. Obviously, very 

large questions about change and continuity intrude 

aggressively. How do we cope intellectually and practicably with the cumulatively gigantic changes that 

unquestionably have occurred in strategic history?

It is necessary to begin with a treatment of the 

most basic questions that can be posed. Probably the 

most fundamental of issues pertains to the distinction 

that one might wish to make between continuity and 

change. Directly posed for the sake of this analysis, 

just how similar in kind are critically important hap-
6

penings in 5th century B.C. Greece to the events in our 

world in the 21st century? We are apt to talk rather 

freely, perhaps even glibly, about the politics, policy, 

strategy, and tactics of then and now, even as if the 

huge differences in thought, behavior, and material 

either did not happen or, at most, are relatively unimportant. Undeniably, a peril of possible historical 

anachronism must loom menacingly over this discussion.10 It is my contention that although material, 

and therefore necessarily tactical, change has been 

continuous, if irregular in pace, over the course of 

strategic history; the larger challenges have remained 

all but constant. There has been, and there continues 

to be, some triangular tensions among technological 

change, tactical ideas on the best way to exploit new 

capabilities, and the cultural preference, assumptions, 

and expectations that often seem to rule important aspects of our strategic security.

The reader of Thucydides today can hardly help 

but notice how familiar the dilemmas and anxieties of 

his world appear to us. It is prudent to be skeptical of 

an easy assumption of likeness between his political 

and strategic world and ours, but, alas, it is even easier 

to be dismissive summarily of apparent similarities. 

It is a considerable aid to understanding if one is able 

to probe for the motive and method behind strategic 

behavior. Such a forensic endeavor is rendered more 

feasible than it might be, certainly intellectually more 

legitimate, if one is prepared to accept as a working 

hypothesis the large notion already introduced here 

of there being a continuous great stream of time. Once 

the awful and awesome Peloponnesian War is placed 

where it properly belongs, as a dreadful episode in 

strategic history, we can see our own experience in 

strategic history as helpful in longer-term temporal 
7

context. What is contemporary for us actually is neither more nor less authentic and distinctive an experience than were the sundry alarms and traumas of 

the ancient Greeks. Of course, threats and dangers 

always are specific to particular circumstances historically, but there is high value in being able, from time 

to time, to elevate one’s gaze above the “threat of the 

week” and the alarm of this afternoon in order to attempt to secure a better understanding of the structure 

and working of the process that produces estimates of 

future menace. Behind the central working hypothesis 

of this analysis, which affirms the strength of strategic historical continuity, is a robustly empirical theory 

that explains the more fundamental reasons for that 

enduring reality.

To understand future threat, it should be realized 

that the 2 1/2 millennia of strategic history fairly accessible to us can and should be utilized in order to 

generate some theory with explanatory power, at 

least potential, over the rich and characteristically 

ever-changing flow of events. Fortunately, we do have 

enough to hand some grip and grasp on the principal 

factors that, in combination, often malign and drive 

our strategic history.11 Specifically, strategic history 

can be approached and understood as the ever dynamic outcome of relations among human nature, political process, and strategic logic and method. It is my 

argument that none of these three broad driving forces 

in history are discretionary. As human beings, we are 

what we are and, effectively, always have been. Cultures have come and gone, but the human nature that 

adopted and adapted them has been all but constant. 

My second factor, political process, has been manifested in a wide range of forms, but we ought not to 

be misled into believing that our species is capable of 

achieving such a perfection of political form that all 
8

questions about threat would become strictly moot. 

Political process is universal because the human condition—Man’s Estate—is ever perceived either to be 

under threat, or at least likely to be so. This intimation 

of menace, in a near or far term, requires making decisions in the interest of alleviating anxiety or actually 

meeting menace. The process of providing for community security is what we understand as politics. To 

provide security, there has to be a political process.12

The details of this process do not really matter for the 

integrity of this argument. Political process determines 

who is relatively the more influential among the concerned citizens, and the more or less well-established 

facts of the local political process confer the necessary 

legitimacy.13 Of course, beliefs and values have varied immensely over the whole wide range of human 

security communities. But, the ubiquity and necessity 

for legitimating political process has been a reality 

throughout all strategic history.

The third and final factor in my austerely economical theory of strategic history is the universal 

necessity for strategic logic and method. By strategic 

logic and method, I mean the approach to challenges 

that endeavors to protect or secure desirable political 

Ends, employing effective Ways, through persuasive 

application of generally coercive Means.14 The basic 

triad of Ends, Ways, and Means needs appreciation 

in the context of the prevailing assumptions, meaning 

beliefs that may or may not be well-founded factually. The strategy triad can look as neat and generally efficient in its glorious inclusivity, particularly in 

PowerPoint form, as actually it is likely to mislead the 

unwary. The basic structure of the theory of strategy 

is as appealing in its wonderful simplicity as it is certain to frustrate in attempted practice. No matter how 
9

persuasive the core triadic theory of strategy appears 

to be, the military practitioner will long remain in a 

condition of ignorance as to the depth and scope of the 

difficult challenges he needs to know how to meet.15

To cite only the most obvious of practical challenges 

that an unduly cursory mastery of the PowerPoint 

presentation of the theory of strategy most likely fails 

to register very clearly:

1. Policy Ends: These are selected as a result of political process, not necessarily on the basis of strategic 

feasibility. These Ends almost always are regarded by 

their political parents as “work in progress.”

2. Strategic Ways: Because strategy is, in its nature, 

an adversarial activity, there will rarely be ways that 

can be presumed reliably ahead of time to be effective.

3. Military Means: Military effect, let alone strategic and political effect, is not definitively predictable. 

Estimation of anticipated nominal and notional capabilities may prove not to offer reliable guidance for the 

future. Strategists sometimes need to be reminded of 

the eternal authority of tactical performance.16 While 

strategy is needed to ensure that tactics are politically useful, it is well to remember that all strategy, 

everywhere and at all times, has to be done tactically. 

Strictly understood, there is no action at the strategic 

level of war, common misuse of “strategic” as an adjective, notwithstanding (e.g., there are no “strategic 

troops,” because all troops behave with strategic effect and therefore logically should be understood to 

be “strategic”).

4. Assumptions: Because the future, by its nature,

denies us reliable knowledge, the defense planner has 

no option but to assume that many, perhaps most, 

of his beliefs will prove to be true enough. Scientific, 

which is to say empirically repeatedly testable, under-
10

standing of the future security context literally is unobtainable. This means that much of a state’s defense 

planning is obliged to proceed on the basis of anticipation, hope, expectation, and possibly confident beliefs 

about the future—which cannot be tested for their accuracy. It is as frustrating as it is important to recognize that tomorrow cannot come on human demand; 

it is always a future wherein currently unexpected 

alternatives may occur.

It is necessary, but by no means in itself satisfactory, to endorse Raymond Aron’s famous praise of 

prudence as constituting the primary virtue in statecraft.17 It is no simple matter to behave prudently. It 

is undoubtedly highly desirable for defense planners 

to be respectful of prudence as a value, even as the 

most important value, but further thought reveals that 

prudence does not come accompanied by advice as to 

behavior reliably applicable to it. It is indeed wise to 

appreciate the relative significance of the consequences of thought and actions, but, unfortunately, the need 

to anticipate consequences requires some capability in 

the field of anticipation and even prediction, which is 

why this monograph now turns directly to confront 

the challenge of possible future threat. How can we 

endeavor to deal with the uncomfortable fact that we 

must cope with an unknown and indeed significantly 

unknowable country—the future?

CONTEXT

The first Bill Clinton administration found itself 

more than marginally embarrassed by the condition 

of unchallenged international strategic preeminence, 

which it inherited from the relatively exciting and 
11

successful George H. W. Bush years. Strategic preeminence had been an aspiration in the Jimmy Carter and, 

even more, the Ronald Reagan years, but it would be a 

gross exaggeration to try to claim that it was seriously 

anticipated, let alone predicted and expected. Far from 

being self-congratulatory at the apparent arrival of a 

somewhat unexpected hegemony, the United States 

and its defense community gave a convincing public 

impression of notable bemusement, bafflement even, 

by achievement of unchallenged and unexpected 

unipolarity. The country had mobilized in the diverse 

ways of grand strategy in order to see off a Soviet 

menace that had appeared to be gaining in strength 

through the 1970s. Under grand strategic pressure, 

however, the Soviet challenge first weakened and 

then nearly vanished during the Bush presidency. The 

United States and its principal allies were counting the 

actual and believed imminent strategic rewards that 

should flow from meeting satisfactorily. Soviet challenge that had been burgeoning since the late-1960s 

died politically, or at least gave almost every appearance of doing so. Of course, there were some prudent 

residual American doubts as to the permanence of 

the change, transformation even, in Moscow, but as 

the 1990s proceeded, it was unquestionable that the 

Soviet demise was a genuine and apparently lasting 

collapse and retreat from imperium.

Although it is exhilarating when the major, indeed 

the only premier-league, menace to national security 

suddenly disappears, it is more than slightly disconcerting and even baffling. The fact that it has happened before—think of 1865, 1919, and 1945-47—can 

offer scant consolation. For more than 40 years, the 

American defense establishment had grappled with 

the certain knowledge that the Soviet Union was by 
12

far in a league of its own—the only serious danger for 

the Republic. One, arguably two, whole generations of 

American officials and Soldiers had understood that, 

ultimately, the United States had only a single enemy 

with which to contend, arguably worthy of respect 

as a near, certainly self-intending, strategic peer: the 

Soviet Union.

For understandable reasons of its geography and 

history, the United States is ill-prepared to cope with 

the problems for national security in these mid–2010s 

and beyond. Of course, the evidence to be provided 

by contemporary history cannot be trusted to suggest 

how we should proceed in our planning and deployments for national and international security. Only 

rarely in the country’s history is there need for a debate on the basic objectives, and the necessary strategy to meet what has become, or plainly is becoming, 

a new situation. It is obvious, for example, that this 

monograph must pause in order to address the evermore pressing issues of national security context. It 

would make little sense to attempt to meet the obvious challenge posed in the title here—”defining the 

future threat”—unless one first can establish just what 

it is that Americans care about that may be threatened, 

and indeed why and how much they should care.

I must confess to surrender to the authority of the 

notional thought that strategic reason and logic are 

intimately engaged with this subject. I assume that 

threats in the future will be no more random than will 

be our organized efforts to thwart them. It is necessary 

not to flinch from risking an apparently exceedingly 

elementary level of inquiry here. It should be obvious that, because I am thinking strategically, I am assuming the authority of an international adversarial 

context. Lurking in this discussion is appreciation of a 
13

fundamental element necessary for such a context. By 

and large, it is sensible to consider the austere theory 

of strategy with its Ends, Ways, and Means in a context of relationships. To clarify: each of the three organizing elements in the traditional formula of and for 

theory requires either a plain notional or more likely 

some actual physical and ideational opposition. My 

immediate destination here is to “pause” or perhaps 

“stop” the definitive political and strategic end to the 

Cold War that menaced our security for more than 

40 years.

Twenty years ago, many people believed that the 

United States had a “unipolar moment” of unpredictable duration.18 Relatively minor distraction in the 

Balkans and in the Middle East continued to frustrate 

U.S. policy and strategy, but such annoyance was not 

judged terribly serious by Americans. Jihadist terrorists emerged from the rubble of erstwhile Soviet ravaged Afghanistan, though more to be noted than really 

noticed as objects of menace requiring urgent political 

and strategic attention. The American attitude in the 

1990s amounted in potential strategic practice to the 

view that the sole remaining superpower does not 

clean windows just because there are no more demanding missions on offer. The all too practical problem for the U.S. defense community in the 1990s was 

a serious absence of political motivation. In political 

effect, in the 1990s, the United States found itself deprived of foreign threat, a condition last enjoyed in the 

early-1930s (though I could register the fact of some 

American hostility toward the empire of Japan following that country’s aggression over Manchuria in 1931). 

While defense professionals will never be caught entirely naked of threat perceptions and concerns, such 

is not the case for the civilian public or, in good part as 
14

an understandable and appropriate consequence, for 

that public’s elected representatives at every level of 

political responsibility. This is popular democracy in 

action, and it was as unmistakable a phenomenon in 

the Athens of the 5th century B.C. as it proved in our 

1990s.19 When an electorate is far less frightened than 

it had been recently, it will expect and, if politically 

necessary, demand that public expenditure on military defense preparation be reduced markedly. In the 

1990s, overwhelming foreign danger, duly conceived 

and not infrequently presented as a threat, seemed 

simply to disappear. Hardened defense professionals 

failed to celebrate unduly but not because their personal livelihoods were at risk. The reason for moderation in celebration by defense experts lay in their conviction that strategic challenge had not been defeated 

definitively, but rather was only resting while new 

contextual fuel for conflict was amassed by troublemakers, familiar and novel.

In a universe characterized more by prudential reasoning than is ours, one could have expected a “1990s” 

decade to be employed as a period of strategic pause 

for the purpose, inter alia, of using the luxury of the 

relaxation of serious security concern, let alone alarm, 

to revisit the fundamental assumptions of American 

grand strategy.20 One needs to bear in mind the fact 

that the country had been fixed in a particular character of response mode for more than 40 years by the 

Soviet threat in its several forms. However, democracies tend not to interpret the absence of acute foreign 

danger simply as a “time out” from conflict as usual, 

but rather as apparently unmistakable evidence of inevitable political progress. Politicians know that they 

will not receive support if their message is one electors do not like. The truth of the matter was revealed 
15

for all subsequent time by Thucydides, of course. He 

knew that history always is punctuated by episodes 

marked by appalling errors in human judgment and 

by chance, as well as by periods characterized mainly 

by prudence in the conduct of public affairs. Proper 

grasp of the implications of the concept of the great 

(and unending and in fundamental effect) stream of 

time can and should protect us both from excessive 

alarm as well as naïve faith that some contemporary 

evidence of political wisdom offers unmistakable evidence of the approach of the long awaited “End of 

History.” Comprehension that history has no end (we 

hope, thinking of residual nuclear concern) also must 

carry with it the understanding that serious national 

security concerns may only episodically be alarming, 

but certainly it will feature repeatedly in the future. 

In short, the United States does not and will not face 

security problems that, once coped with adequately, 

must be followed by an endless ever improving period of peace and prosperity. The political and moral 

context for this discussion has to be assumed to be one 

of eternal periodic alarm in varying degree. This is the 

permanent reality of all strategic history, the American included. It is, and must remain, a strategic history and is not to be confused with a fairy tale that 

climaxes with a definitively happy ending.

As a matter of empirical record, the decade of the 

1990s that should have been characterized as a strategic pause that allowed for a reconsideration of national 

grand strategy instead was a decade marked by technical and largely tactical obsession with the promise 

that there might be in digital information technology. 

For the better part of 10 years, in effect, the American 

defense community all but squandered its inevitably 

temporary unipolar moment, self-obsessively contem-
16

plating how tactically formidable it might become as 

a result of digitization.21 The revolution in military affairs (RMA), military revolution, and military technical revolution collectively were treated as being the 

strategic flavor of the decade. The inattention to more 

serious matters of policy and strategy was revealed in 

painful form in the political and strategic errors that 

succeeded September 11, 2001 in the counterinsurgency (COIN) decade of the 2000s. Digitization in its 

many applications has proved, unsurprisingly, to be 

of high tactical importance. The problem cited in this 

section on context essentially has nothing to do with 

the ever greater technical and tactical exploitation of 

information technology, but rather with the subjects 

of yet higher professional concern to us that have been 

neglected unduly in the fields of strategy and politics. 

In noteworthy part, the neglect was, seriatim, of obsession with the exciting technical and tactical promise 

in RMA, and then with the challenge of attempting to 

counter terrorism and insurgency in distant and culturally ill-understood lands.

The better historians among us have tried to advise 

that policy and strategy inherently are relatively more 

important than are technology and tactics.22 This does 

not amount to the claim that tactics are unimportant, 

only to the proposition that strategic history has demonstrated that, while tactical and much technical error 

proved correctible and survivable, almost invariably, 

political and strategic mistakes were fatal, no matter 

how worthy the ultimate political and moral intentions may have been.
17

SPECTRUM OF CONCERN

Unless there is unmistakably good evidence suggesting the probability of particular threat in the future, it is necessary to recognize the fact and impressive degree of uncertainty that is in the nature of this 

crucial subject.

Capability and Intention.

Threat should be defined as an intention to do 

harm that logically and practicably requires command 

of the physical ability. As a general rule, threats have 

to be received clearly enough by their intended addressees. However, both common sense and strategic 

historical experience suggest that the unambiguous 

delivery and receipt of threats also are necessary if 

they are to perform the function intended by their 

authors. More to the relevant point and as the theory 

behind nuclear strategy long has sought to explain, 

the credibility of some threats almost necessarily will 

long be in doubt.23 It is important not to forget that 

threat manufacture, transmission, receipt, and interpretation is always an essentially human enterprise. 

The deadly (nuclear-armed) machines of mass menace that compass the crown jewels of potential threat 

projection will be inert instruments that function 

awesomely only as a result of the outcome(s) to human adversarial behavior. This whole discussion of 

threat and responses to it is suffused with recognition 

of the salience on both sides of distinctively human 

thought and behavior.24 Nearly all military capability lends itself to some potential mission of coercion, 

though most of the time and in most places inherent 

ambiguity about motives for employment simply re-
18

mains as a strategically valuable residual quality of 

military power.

It is usual to define threat with usefully pointed 

economy as being well enough expressed by the formula: threat = capability x political intention. There is 

virtue in this austere expression, but little additional 

thought is required in order to understand that political intention does not usually remain constant for long. 

In other words, this simple formula may well mislead 

us into regarding as constant what in reality usually is 

anything but. Without wishing to divert this analysis 

away from its central theme of “threat,” nonetheless, 

it matters deeply that readers understand fully that, 

in strategic history, most of the time, policy Ends are 

not fixed permanently. Because conflict and war are, 

in practice, kin to organic happenings that wax and 

wane often unexpectedly as they develop, so policy 

Ends quite typically will need to be adjusted in order 

to reflect a clearer more contemporary understanding 

of what appears to be possible.25

To extend the point just registered about usual 

fluctuations that characterize policy and its Ends, it 

is necessary to accept that this whole subject is liable 

to real-time adjustment, even on items widely held to 

be of fundamental significance. Perhaps the easiest 

way to explain what I mean is to contrast the austere 

formal architecture of strategy with the reality of strategic behavior in historical practice. Whereas one can 

teach that strategy entails the pursuit of politically 

agreed policy Ends, by suitable strategic Ways, employing the necessary military Means, students also 

need to have a secure grasp on how theory actually is, 

and has always been, practiced. In reality, each basic 

element in the simple strategy formula—Ends, Ways, 

and Means—is ever likely to be in need of adjustment 
19

for a better fit with changing circumstances and adaptation in vital detail.26 The argument was made earlier 

that the “Ends” of policy should always be regarded 

as potentially being only a “work in progress” as contrasted with some conclusive vision of intention. In 

fact, the same tolerance of some flexibility is necessary 

in regard to each of the big three categorizing concepts—Ends, Ways, and Means. Governing this whole 

discussion is the eternal and ubiquitous truth that 

statecraft and strategy are in the realm of what proves 

possible to achieve, not necessarily of what ideally it 

may be highly desirable to accomplish. Strategic history demonstrates clearly that defense planning as a 

pragmatically prudent matter always requires us to be 

satisfied with “good enough” solutions.27

The professional soldier typically favors precision 

and consistency on the part of political superiors. This 

liking for a clear, definite, and preferably unchanging 

strategy cannot guarantee delivery of a steady and 

well-directed military effort, but it should help.28 The 

politician who is a policymaker is more likely to regard 

politics and political effect as the home of Ends, rather 

than the policy that he hopes will serve adequately to 

support the politics. In other words, while the soldier 

understandably tends to view policy objectives as 

his relevant Ends, with political process holding on 

a secondary role, the policymaker typically regards 

politics and its process as the true authority, albeit one 

expressed and explained in commonly (but permanently) temporary policy terms. The better definitions 

of strategy take care to specify, at least to suggest, the 

superior role played by political process in the making 

and execution of strategy. My own preferred definition risks erring on the side of explicit recognition of 

the relative but clearly superior importance of politics. 
20

I choose to define military strategy as “the direction 

and use made of force and the threat of force for the 

purposes of policy as decided by politics.” The context for political activity and decision is fundamentally different from that for military decision. It follows necessarily, though commonly unappreciated, 

that the understanding of future threat also is likely 

to diverge as between the different worldviews of the 

professions of politician and soldier. Of course, threat 

definition requires military analysis, but it is necessary 

to remember that soldiers are not usually in charge of 

a country’s statecraft. Statesmen are politicians who 

have succeeded in playing the game of relative political influence more successfully than have their rivals.

An important migration in conceptual meaning 

concerning strategy occurred in the 19th century, but 

it is not as well understood as it needs to be. Specifically, the core meaning of strategy in the 1820s was 

that its purpose was to direct choice of and for battle 

in its expected consequences in war. In noteworthy 

contrast, strategy came to be regarded post-World 

War I primarily as a support for politics and its policy in peacetime and wartime. Modern strategy has 

not lost its erstwhile battle focus, but that fixation of 

Clausewitz’s day has been conclusively widened in 

political scope.

As often as not, there will be a vital quality of ambiguity about actions and words intended to carry 

menace. Professional soldiers favor, perhaps need, 

definite orders and commands, the dangers associated 

with it which can be calibrated by some military calculation. But, the politician, in his characteristic universe, wants to be able to advance further or to retreat 

with minimum political embarrassment. Indeed, the 

political leader can be endangered by self-deception 
21

that may confuse his strategy. Because they act preeminently with and through words, politicians are prone 

to misread the scope of feasibility in policy zones that 

transcend the world of politics. This danger understandably is especially acute in the relations between 

politics and war. In fact, although all war is political 

in meaning for all time, it is not an integral branch of 

politics. Although war should serve politics, war is not 

politics, notwithstanding the migration in meaning of 

strategy noted previously. There is a permanent need 

for currency conversion between military threat and 

action and desired political effect. Although threat to 

American security can be so obvious as to be all but 

unarguable, that reliable, if still uncomfortable, relative stability in assumption about foreign menace is 

by no means dominant in our contemporary threat 

analysis and divination.

There is little room for doubt that Thucydides’ 

understanding of the causes of the great war of his 

time between Athens and Sparta can offer guidance 

superior to the alternatives from our contemporary 

social science.29 In political life, both domestic and international motivation inevitably is always complex 

and therefore potentially complicated and ultimately 

indeterminate if one looks foolishly for a scientific 

quality of evidence. But, if we choose to be content 

with high plausibility of fit with what is known with 

substantial confidence about political context, it is possible to identify probable motivation of the causation 

of events. It should be recalled that threat has been 

defined here as a product of capability multiplied by 

intention. In other words and by way of example, a 

force of intercontinental ballistic missiles is naked 

of any specific strategic meaning until its political 

owners decide upon such. 
22

It is worth noting that, over the past century, many 

scholars and politicians who should have known better gave robust indication of their failure to grasp the 

essential point just registered here. The whole modern history of arms control has revealed confusion of 

understanding about the significance of arms in their 

relation to political intentions. Identity of political 

ownership of weapons largely, though not absolutely 

invariably, is key to understanding strategic and political meaning. Military capability may well be rich 

in strategic, operational, and tactical implications, but 

the ascription of threat depends upon the political 

ownership of the instruments of interest. Of course, 

such ownership often will be innocent of malign intention, or at the least will only be deemed likely to be 

contingently menacing. 

Since context typically drives contingency, and 

given that context should lend itself to influence by 

behavior that shapes political judgment, the grim possibilities that one can identify with particular inert 

military items may serve as providing timely warning 

for statecraft. Episodically throughout recorded strategic history, developments have been interpreted as 

being in an adversarial context, and the identification, 

possibly misidentification, of great security threats 

has ensued. 

Thucydides was a deep and subtle analyst of the 

meaning of his times, and he expressed little doubt 

about the primary cause of the great war that was the 

ruin of ancient Greece. The Athenian historian (and 

failed general) acknowledged the many complaints 

that Athens and Sparta lodged against each other, often with some justice, but he declined admirably to be 

distracted even by particulars, admittedly contributing to the main thrust of his narrative and the clarity of explanation that he sought to convey. In words 
23

alive with meaning for all subsequent periods, especially for ours in the 21st century, Thucydides wrote 

as follows:

To the question why [in 431 B.C.] they broke the treaty 

[the Thirty Years’ Peace of 446 B.C.], I answer by placing first an account of their grounds of complaint and 

points of difference, that no one may ever have to ask 

the immediate cause which plunged the Hellenes into 

a war of such magnitude. The real cause, however, I 

consider to be the one which was formally most kept 

out of sight. The growth of the power of Athens, and 

the alarm which this inspired in Sparta, made war inevitable. Still it is well to give the grounds alleged by 

either side, which led to the dissolution of the treaty 

and the breaking out of the war.30

The Athenian Empire demonstrated an intolerance 

of political and strategic dissent from its client allies 

and certainly inadvertently provided ample fuel for 

hostility. However, as Thucydides recognized and acknowledged, the security problems for Athens in the 

longer term was fundamentally the immoderateness 

of her power as perceived by other Greeks, and then 

all too naturally the unmistakable evidence of an overweening confidence evidenced in Athenian policy and 

strategy as an easily traceable consequence. But, what 

is the relevance of the Athenian case to the American 

defining of future threat? Indeed, is there any relevance 

worthy of much note? The most pertinent problems for 

American security need to be understood as political, 

though there is a major, perhaps even overwhelming, 

systemic complication. Through all of strategic history 

to date, the principal and indeed enduring threat to 

security has lurked in unbalanced power. Balancing 

power cannot guarantee peace and tolerable prosperity, but we do know that the evidence proved by 
24

unmistakable historical cases of unbalanced power, or 

certainly the fear of such, inherently are hostile to that 

peace and prosperity.

Unfortunately, the Thucydidean worldview,which 

was and remains all too realistic, tells us that our future security is certain to be threatened by the usual, 

indeed normal, working of the politics of international life. The distinctive advantages and benefits 

that America enjoys are collectively the motive that 

will find expression in future threat. This is not quite 

to suggest that the sense of hegemonic preeminence 

and duty that led the United States to endeavor to 

sustain a non-Communist South Vietnam in the 1960s, 

and a generation later to redirect and re-make Middle 

Eastern and then Central Asian history in Iraq and 

Afghanistan, was unworthy. But, it is to suggest that 

it was unwise. Prudence in policy is much easier to 

locate in historical retrospect than it was at the time. 

Frequently in strategic history, good intentions have 

been permitted to masquerade as prudence. For the 

record, even near-term achievable political and strategic results cannot necessarily be trusted to deserve 

judgment as prudent.

Risk and Danger.

Virtue and villainy do not bring their most appropriate consequences inevitably, but it is prudent to assume that such might be the case. Notwithstanding its 

continuing relative greatness as a superpower, questions fundamental to this discussion have to include 

the following: What will be the political context for 

America’s definition of threat in the future; and what 

might America strive to do to exercise some helpful 

measure of influence in, perhaps even control over, 

that future political context?
25

There is good reason why time plainly has to be 

understood as comprising the least forgiving of strategy’s many dimensions. The temporal factor is inalienable as a critical element in all defense planning. Although this has always been true throughout strategic 

history, never has it been more vitally salient than today. Defense planning must be geared for tolerable fit 

with the anticipated timing of foreign security risk and 

danger. Indeed, it should be all but second nature for 

planners to be able to categorize menaces to national 

security on a time scale from current alarm through 

near- and medium-term worry and serious concern, 

to the more agreeable distant horizon of anxieties 

about the relatively far-term future. Future security 

threats are anticipatable, let alone predictable, only 

with diminishing confidence, as one ventures necessarily and somewhat imaginatively into an evermore 

distant future. 

Moreover, if particular political antagonism and 

hostility is less than confidently predictable, it is difficult to specify possible or probable measurements 

attached to the strategic future. When the political 

context changes, so must the strategic one. Given that 

strategic meaning is conferred by political effort, it is 

obvious that exercises in military-technological futurology are likely to miss most of the needed argument 

concerning prudent defense provision. However, 

contrary perhaps to a line of reasoning that would 

privilege an undisciplined openness of strategic competition, this discussion is sustained by the conviction 

that there is and will remain what can be regarded 

as a categorical imperative shaping of international 

political and strategic competition. Without quite endorsing a fully deterministic view of the terms for the 

future security of America, nonetheless there are sub-
26

stantial grounds for confident identification of principal strategic historical markers of the policy passage 

that need to be pursued in the interest of prudence. 

It is advisable that I remind readers of the genuine 

uncertainties and possible challenges that our defense 

planners have to recognize and work around, if not 

overcome. At some risk of encouraging pessimism, I 

would not endorse seeking to define future threat. The 

United States has to be able to cope with the following 

uncertainties:

• Identity of menacers (or possibly threateners)

• Seriousness of menace

• Time horizons of menace

• Feasibility of adequate response (e.g., time, cost, 

likely consequences).

Contemporary uncertainties must preclude the 

kind of exercise in threat definition that can produce 

all but tangible and convincing answers. It must follow, therefore, that the relevant challenge to the U.S. 

Army should not primarily be one of threat predictions and spotting! The reason why Thucydides’ great 

book figures so significantly here is not because I am 

striving to assert the relevance of an ancient Greek historical analogy for today and tomorrow, but rather because the context of competition concerning security 

is so categorically analogous. The differences between 

5th century B.C. and today are indeed enormous, but 

so are the similarities. Aside from the quality of catastrophe that we must assume would follow nuclear 

use, there is little about the relations between Athens 

and Sparta that is notably mysterious to us today. 

However, what matters most for the subject of this 

discussion is the plausibility that the political and 

strategic relations among the greater powers have not 
27

altered fundamentally since that now distant period. 

This is a vitally important subject about which to theorize and argue, because it bears with maximum directness upon the issue of whether or not strategic history in the great stream of time can provide sufficient 

evidence of empirical examples of interstate behavior, 

prudent or foolish.

The study of history shows us what can happen, 

which we know for certain because it has happened. 

It is not available as a reliable guide to accurate prediction, because the course of strategic history is subject to too many and too diverse a range of possible 

influences, not least the ever potentially individual 

human, to provide adequate fuel for confident prediction.31 The United States should not seek, because it 

would not find, specific instructions in Thucydides as 

to what should be defined as threatening. But, what 

it can and should find is education both on how great 

powers behave and what the hazards may prove to be 

in that behavior. The definition of future threat should 

encourage prudential defense planning in line with 

the country’s desired, albeit self-disciplined, role and 

responsibility in the international system. 

Risk and danger cannot be eschewed and thereby 

avoided conclusively, but the whole record of strategic 

history offers education in the high value of balancing 

power. I must add hastily that history also warns of 

the practical difficulty in achieving such balance, and 

especially of the risks and danger that are apt to beset 

the pursuit of immoderate greatness. Preeminent unilateral hegemony will always be challengeable sooner 

or later, typically the former, but it need not be effected in a power transition process fatal for world order. 

Power transition necessarily has characterized all of 

strategic history, but to date, of course, it has never 
28

been coerced or negotiated in the context of nuclear 

armament. American preeminence as a, and then the 

only, superpower for a while in the 1990s is particularly peril-prone both because of its nuclear backstop and 

the reluctance or even inability of many Americans to 

see themselves as they need to in the great stream of 

human history. U.S. superstate prominence has been 

a physical and psychological reality since 1943–44, 

but this reality requires understanding as a passing 

dynamic episode contextual in history.

When, as here, we think about future threat, we 

have to consider how the United States may best continue to perform a benign hegemonic role in international security. There is a problem in that Americans 

have difficulty understanding that their country, notwithstanding its unique features, in the last analysis 

simply is yet another state that has no practicable 

choice other than to play the game of nations along 

with everyone else. There is only one game, and it has 

proceeded through all of strategic history from the 

time of Athenian and Spartan competitive preeminence until today. Contemplating the future threat to 

security, we should proceed unconfused by our domestic ideology of uniqueness. Future threat will lurk 

in the malign influence of foreigners’ fear, their energetic determination to protect their reputations, and 

in their definition of national interests that may not be 

compatible with our own.

Thucydides wrote about the great war of his lifetime, on the safe assumption that there would be other 

great wars in other times involving other polities. He 

was unsparing of human folly and error, and he believed that his revelation of such might have some 

useful benign educational effect. Following the Greek 

author in spirit at least, I believe that a robustly and 
29

sufficiently evidenced grasp of how states need to behave in order to balance power is key to preserving the 

international order vital to future security. Ironically 

perhaps, America’s ability to define future threat in a 

way conducive to the protection of important values 

is hindered by the experience and legacy of extraordinary national hegemony. This is understandable, even 

if not well understood currently. An important source 

of difficulty lies in the relative modernity of active 

American participation in the game of nations. The 

genuine risks and dangers of the Cold War served in 

practice to hide the fact that the great Soviet–American Cold War was far from unprecedented in strategic 

history, save only for the uniquely challenging addition of weapons of mass destruction to the equation of 

high risk.

It would be misleading to characterize effort for 

the future threat definition as an attempt to return international politics to a more normal multipolar condition, following the decades of bipolar Cold War, the 

unipolarity of the 1990s, and the unprofitable, if wellintentioned endeavors to remake backward realms 

in the anti-jihadist 2000s. But, given that the United 

States was not a very serious player in international 

politics prior to World War II, it is scarcely surprising 

that the country has relatively little understanding of 

how and why international politics are played as they 

are. Contrary to appearances, this is not meant to be 

critical. American statecraft culturally is what it is, reflecting somewhat the novelty of the national experience. This discussion does not seek to engage combatively with an American culture that reflects somewhat 

the dominant national experience.32 The challenge 

here is to explore the best way the United States, with 

its distinctive and quite recent historical experience, 

can cope with the challenge of defining future threat.
30

A key reason why it is advisable to accept the concept of prudence as having merit superior to alternatives is because it is the idea that most exactly captures 

the critical difference between a risk and a danger. 

Moreover, prudence is a concept that, in theory at 

least, suggests in its required focus upon consequences how potential dilemmas should be approached and 

met. Unfortunately, causes for concern in international politics do not appear on policymakers’ desks helpfully labelled either as risky or dangerous, while their 

actuality or their potentiality for harm may well encourage uncomfortably subjective and unmistakably 

uncertain threat assessment. It is prudent to be clear 

in one’s own mind about the distinction between risk 

and danger, albeit while ascertaining the necessarily 

subjective character of the judgment offered. Logically, a risk is a potential way station that can be en route 

to another condition, which one may well judge to be 

dangerous. Given that danger is a realized condition, 

accurately perceived or not, risk has to be regarded 

as a quality contributing to the maturing of incipient 

peril. Plainly, the ascending peril between risk and 

danger is captured adequately in the language used. 

Where the idea of prudence intrudes most usefully is 

in its ability to suggest persuasively that there is a vitally important difference between the two. Poor statecraft and strategy, unaided by the insight required by 

and for prudence, will be prone to conflate risks and 

danger, with the result that we may miss important 

possibilities for the control of escalation in menace.

Because of its significantly open nature, the concept of the future lends itself easily to abuse by theorists who are not careful in their choice of words, either because of what may be attributed to mischievous 

aforethought or, more likely, simply because they are 
31

theorizing beyond their normal comfortable intellectual depth. One reason we should seek to discipline 

our choice in conceptual usage is because we do not 

know the best way to influence the future: at the very 

least, we should take care to avoid misusing concepts 

that might do unanticipated damage to our security. 

The problem most central to this discussion is the unavoidable fact that we are unable to foresee the future. 

When our intelligence community looks forward in 

time, it is trying to identify the consequences of past, 

current, and future historical phenomena. A determination to be alert to consequences translates as a 

commitment to prudence. Such a commitment does 

not necessarily mean the attempted eschewal of risk, 

including ones that could be dangerous on any reasonable assessment. Instead, what would be meant, 

certainly implied, is that the possible consequences 

of our behavior, positive and negative, would be considered seriously. Given the unavoidably speculative 

nature of all futurology, it is always more or less difficult to ensure that political and strategic decisions 

about the future that are popular are subjected to 

honest assay.

The defining of future threat is a behavior exceptionally inviting to the ill-deserved authority of hope 

over realistic expectation. This discussion now must 

address key issues pertaining to assumptions and 

evidence that should not be permitted to slide out of 

sight inadequately treated.
32

When Is a Threat Not a Threat? Assumptions 

and Evidence.

Probably the soundest judgment on the general 

problem of threat definition for the future was drafted 

a generation ago by Professor Klaus Knorr of Princeton University. The professor advised with these wellconsidered words:

The act of threat perception creates an image of reality; it is a device, a hypothesis. Indeed, this holds true 

of all perception. All human awareness is a personal 

construct, something that we organize. It is a set of 

assumptions that deals with the outside world selectively, focusing on some components while screening 

out others. We continuously “bet” about the nature 

of reality. Preexisting assumptions (i.e., theories) 

about the outside world help us to select our “bet.” 

But for this very reason, they hinder, as well as help, 

perception.33

The other intellectual difficulty vis-à-vis threat 

perception is that it concerns the future, and often 

not just the immediate future. There is no information whatever about the future. The political and social phenomena that are objects of threat perceptions 

change over time. Even if we know what is true today, 

we could not know what will be true tomorrow. As 

historical accounts demonstrate again and again, state 

behavior is highly unpredictable. It can change suddenly; surprise is frequent and not rarely dramatic. All 

we can do is speculate on the shape of future events 

by studying the relevant (especially the recent) past. 

The mere projection into the future of what we have 

learned about the past already has been pointed out, 

is extremely hazardous.
33

Defining future threat is a speculative enterprise 

that invariably requires the making of decisions on 

our part that quite literally cannot be justified with 

reference to hard and definite evidence. For the defense planner, the future is a foreign country overpopulated with situational possibilities abundantly full of 

threat potential. Because the United States is choosing 

to remain a (if not the only) global superpower, the 

threat horizon of the future is well populated. But, we 

need to ask, just what is a threat and what makes it 

so? Because the subject lies in the future, there cannot be direct evidence of such threat. What is available, however, is contemporary and recent evidence 

of behavior and, at least inferable, policy motive, set 

in the long-term historical context of our understanding of the politics of statecraft. We can know with 

tolerable reliability what states have done or sought 

to do recently, and we can speculate with some confidence about the likelihood of contextual continuity in 

respect of American interests that may be menaced. 

However, what we cannot do is predict and expect 

“Black Swan” events or episodes that are, by definition, highly improbable yet potentially and systemically very disruptive in our context of most concern 

here to the American threat horizon.34 A Black Swan 

is an event as unexpected as it proves profound in its 

consequences. Such occurrences are as startlingly surprising as they are seemingly transformative of prior 

patterns in near habitual behavior.

It seems unlikely that the outside world will come 

in haste in the near term to the political rescue of 

American threat definition with respect to its Army. 

Menace to particular American interests is locatable 

worldwide but, both fortunately and unfortunately, 

currently there is not a single dominant threat filling 
34

the horizon. The most prudent conclusion to draw 

from the current international security context needs 

to be a distinctly unheroic, but defensibly sensible, determination not to bet extravagantly on any particular 

category of strategic challenge. The U.S. Army has 

endured turbulent recent decades of late.

1. In the 1970s, it sought to recover from the diverse but heavy damage suffered in Vietnam.

2. In the 1980s, it was adapting and adjusting both 

to exciting new technologies (still largely prospective) 

and to a Soviet threat in Europe that had matured and 

expanded since the late-1960s.

3. The 1990s saw the Army seeking to make some 

sense of the highly fashionable RMA and later the 

transformation possibilities and debates, but the absence from the near horizon of a major dominant military threat considerably undermined the plausible relevance of expert proposals about the technical-tactical 

frontier and beyond.

4. The 2000s witnessed and appeared to require 

the return of counterinsurgency. COIN rode again, 

not least in counterterrorist regard, in the sharpest of 

contrast to the Army’s foci in the two previous postVietnam decades.35

In summary form, the U.S. Army has experienced 

decades of: recovery and reform (1970s); modernization for high-end warfare (1980s); fundamental uncertainty and retreat into technical visions of RMA (1990s); 

and COIN and counterterrorism (2000s). The point 

that really matters in this discussion is not any particular focus and the political policy and strategy behind 

it. Rather, it is the fairly obvious lesson that policy, 

particularity with strategic choices for the Army in the 

future, cannot be anticipated with high confidence. It 
35

would be hard to design strategically more distinctive 

decades of dominant experience for the U.S. Army 

than those experienced from the 1960s through the 

2000s. The politically dominant strategic reality for 

the Service was radically different from decade to decade. This is the historical context for consideration of 

future threat definition. More to the relevant point is 

the function performed for us by Thucydides in his 

Peloponnesian War, given the transhistorical theory of 

state behavior that it carries. Thucydides cannot tell us 

what, or even might, emerge as a threat to security in 

the remainder of the 21st century, but his understanding and explanation of how and why states behave as 

they do has profound advisory implications for our 

contemporary choices in policy and strategy.36

Because of operation of the laws of physics, we 

can secure no grip upon future happenings, no matter 

how convinced we may be in their anticipation. But 

what we can know about the future should prove sufficiently serviceable to allow for prudent choices on 

the shape and composition, size, and equipment of the 

Army. With much gratitude toward Thucydides, and 

also as a result of careful study of strategic history, we 

can identify prudent choices in military posture. This 

is not a simple matter, because the would-be threat 

definer, perhaps diviner, needs to be fully alert to the 

following: the power of accident; strategy’s adversarial nature; Black Swan possibilities; enduring human 

tendencies with conflictual implications (e.g., political 

process and the implications of fear and anxiety); and 

the potency of needful ambiguity inherent in much 

about defense planning and preparation.

It is commonplace, indeed it is only sensible, for 

defense plans to be specifically contextual to the point 

of potential political embarrassment. Defense plan-
36

ners as strategists necessarily inhabit a world wherein 

there are enemies, certainly adversaries, and threat 

possibilities in the day after tomorrow, if not tomorrow itself (else why conduct the planning?). However, 

even though threat definition can carry some risk of 

being self-validating as military professionals simply 

perform their professional task of preparing for what 

might happen, such preparation is only prudent. It is 

important not to forget that the concept, and indeed 

the principle, of prudence in defense planning means 

that one must be alert to the dangers that could lie 

as consequences derivative in part from errors in the 

plans. Because it makes no sense to seek from the military an understanding of the future that it cannot obtain as a reliable certainty by any known method, we 

have no practicable alternative other than to settle for 

an understanding of future strategic need that should 

be able to rest well enough on our comprehension of 

the past. We should seek to identify what scholars of 

strategic history suggest is possible, if not probable. 

Also, we need to appreciate that, although each period in history may have its own distinctive pattern 

in events with plausibly presumable motivation, such 

distinctions are only differences in character, not in 

nature in the great stream of time.

Learning from History.

 History teaches nothing; it is not an agent with 

motives active on the course of events.37 But, history 

is by far the best educator for our strategic future.38

While we cannot and must not hunt earnestly, though 

inevitably failingly, for historical analogies to our 

emerging challenges, we can and should seek assistance, perhaps inspiration, in the intellectual construct 
37

known as the “historical parallel.”39 What is claimed 

using this concept is that the course of events “then” 

(i.e., whenever) would appear to have shown important features in common with a contemporary track 

of events of our own recently. To hazard a theatrical 

comparison, what we would be suggesting would 

be that much of the state setting appears substantially common to “then and now,” while probably 

also today’s adversarial contest appears to have had 

antecedents in motive and perhaps even in results 

in past periods. The episodically protracted British 

strategic experience on the northwest frontier of India is a compelling example of a strategic context that 

could be regarded plausibly as historically noticeably parallel to the situation in Helmand Province of 

Afghanistan in the 2000s.40

I am careful to distinguish between the analogy 

and the historical parallel, because the former is fundamentally empirically unsound. History does not 

repeat itself in ways essential for analogy to deserve 

authority, but most certainly in contrast, it does repeat 

itself in the situations that its strategic course poses 

to policymakers and strategists. It would be difficult 

to exaggerate the significance of this distinction. To 

recognize an apparent case of historical parallelism is 

to notice similarities that may be important between 

the cases from different historical periods, but that is 

all. Unfortunately, analysts often latch on to obvious 

common elements (e.g., Kandahar in the 1880s and 

the 2000s) between historical episodes in the hope of 

discovering keys to past success or failure by (inappropriate) analogy. Strategic history simply is too varied in its dynamics and its changing contextual detail 

for analogy to serve as a valuable source of guidance. 

There is no alternative to the securing of detailed con-
38

temporary contextual knowledge. Old methods cannot be relied upon to continue to be true, if they ever 

were, just because they may have been well tried in 

the past.

My intention here is not to condemn or even discourage efforts to seek educational value from understanding the course of strategic history; it is only to 

advise that such value cannot be found by attempting to analogize in detail from times past. There is 

no adequate substitute for current knowledge of the 

details that change. We can and should learn from 

history about the nature and even the character of future threat. Threat always matures and emerges from 

causes inherent to the nature of international politics, 

its statecraft, and its strategy. Thucydides knew and 

could explain this in the Athens of the 5th century 

B.C., and his explanation reads convincingly for our 

era also. What does promote great confusion is the 

popular tendency to neglect the difference identified 

here as that which lies between the nature and the 

character of threat. Probably it would be more accurate to focus on the enduring reasons why threat is an 

eternal problem, though arguably it is most usefully 

considered with reference to its nature. 

The point of overwhelming significance for this 

discussion simply is that threat—past, present, and 

future—is a persistent phenomenon, one consequent 

upon the enduring need for provision of human security, expressed in political systems that organize for 

collective protection. Distinctive polities must exist 

in a whole world of politics, and the relations among 

them have always been prone to aggravation and 

anxiety, occasioned by concerns about security. As 

American defense planners confront the empirically 

more than marginally mysterious future, they know 
39

for certain that anxiety, and periodically even some 

alarm, about national security will characterize the 

future. There will be no conclusively happy ending 

to security fears. The precise character of such alarm 

cannot currently be anticipated reliably, but the defense community has to be alert to their probable and 

even possible manifestation, as well as to the causes of 

anxiety that are actual and current. Important though 

contemporary details of plausible menace certainly 

are, it is scarcely less significant to grasp the fact of 

the certainty of change. Future threat, both empirical 

as physical hardware and also as foreign intention in 

our perception, is always in process of some change. 

The definition of threat changes constantly community-wide. Probably more often than in the physical 

respect, threat definition shifts as a result of changes 

in political evaluation.

It may be recalled that much earlier in this monograph, I deployed the familiar bare formula that notionally identified threat = capability x intention. The 

former typically takes considerable passage of time 

and notable expenditure of effort to achieve, while 

the latter can change in a matter of hours. That is 

not very helpful for would-be scientific appraisal of 

intensity of threat level, but it is essential to grasp 

as contextual reality. Notwithstanding some of the 

aspirations for certainty of knowledge by social science, threat definition and analysis must ever remain 

an art. Just as governments, let alone key individual 

statesmen, cannot make vital decisions based upon 

a true certainty of knowledge of probable consequences, so definition of threat to national security 

must always ascend, or descend, to being a matter of 

human judgment.
40

The strategic history of times past, both far and 

relatively near, cannot provide a reliable source of 

evidence as to what should or should not be defined 

as a future threat to the United States. The reason is 

because contextual detail must be as significant in 

the future as it was in the past. It is the beginning of 

wisdom for defense planners to understand why they 

ought not seek the literally unknowable. National security planning today cannot sensibly aspire to find its 

logic on much understanding of, say, the second half 

of the 2020s or of the 2030s; that might be deemed reliable. But, fortunately, such understanding, especially 

of particular menaces, is not necessary for American 

defense planning to be judged tolerably prudent. Unquestionably reliable detail concerning future threat 

neither exists nor can be generated, given the rarity 

as well as the scale of the unknown (including the 

“unknown unknowns”).41 Consequently, our defense 

community should be satisfied to be guided by an understanding of possibilities, especially of those that 

current context and recent events indicate as belonging close to what can be categorized as probabilities. 

This is what should be understood by a prudent approach to national security. Preeminently, prudent 

definition of threat to American national security has 

to be an exercise in the analysis of a reasonable projection of the consequences judged probable, or certainly 

possible, that would follow as a result of serious error in defense planning. To repeat, this is art rather 

than science.

Probably the definitive terse explanation of state 

behavior was offered by Thucydides in his rendering 

of the Athenian reasoning behind its impressive, if ultimately fatal, bid for undue imperial greatness. In the 
41

Athenians’ attributed words (of 432 B.C., just prior to 

the war) provided by Thucydides:

That [Athenian] empire we acquired not by violence, 

but because you were unwilling to prosecute to its 

conclusion the war against the [Persians] barbarians, 

and because the allies attached themselves to us and 

spontaneously asked us to assume command. And 

the nature of the case first compelled us to advance 

our empire to its present height; fear being our principal motive, though honor and interest afterwards 

came in.42

When we contemplate the international political 

and strategic context of this 21st century, it is only prudent for us to be alert to the need for a wisdom in national security planning that should be ready enough 

to cope with challenges to the United States that probably will be ineradicable from the context of contemporary international relations. Even if a Thucydidean 

fear does not grip the United States, it has to be judged 

likely that such a dangerous condition of anxiety may 

well grip Beijing or Moscow, of course, with potentially dangerous consequences for us. Such fear has been 

lethally, if episodically, characteristic of most international political systems, not least among them our 

own. It must be a duty of our threat definers to seek to 

encourage provision of American response that is both 

adequate in discouragement of hostile initiatives and 

likely to prove encouraging of moderation abroad. At 

this present time, we do not know how smoothly a 

process of power transition between the United States 

and China will be for either side. In truth, neither a 

crystal ball nor historical scholarship can be of much 

assistance to American defense planners today: the 

strategic future is not knowable in important detail. 
42

However, we do know of the need to be alert to the 

danger in a major process of international political 

transition of power. Prudence, as a guiding light, is 

the basic requirement for our national security in the 

decades ahead. Threat definition will change in character of detail, but a fundamentally prudent American 

national security posture should be well able to cope, 

notwithstanding the uncertainty in anticipation.

CONCLUSIONS AND RECOMMENDATIONS

Prudence and Ignorance.

Because the future is unknown and unknowable in 

detail, it is the duty of the American military establishment to be as ready to confront and defeat threats as 

society’s contemporary political support allows. The 

ability to define future threat is not a skill that can be 

taught. Highly relevant, indeed vitally necessary, data 

is missing. Prudence is the most useful concept that 

should be adopted as the idea most fitting for authoritative service in the current era. A prudent defense 

must be one tolerant of some error. The United States 

cannot promote its global interests equally regardless of character and intensity of menace. But it can 

and should be ready to respond to broad categories 

of security challenge. Just how broad is a matter for 

political decision superior to that under consideration 

here as threat definition. It has to be understood that 

there are two distinctive, albeit related, aspects of the 

future threat challenge. On the one hand, there is the 

necessity for Americans to decide what is and what 

is not a threat, as contrasted with a risk or residual 

source of danger. On the other hand, it is necessary to 

understand what might be done about the apparent 

menace in question. 
43

Because it remains the global superpower, the 

United States is exceedingly reluctant to appear indifferent to the security anxieties of its clients. The United 

States is learning today what has been true at all times 

and in all places in the past, that the sovereign “working level” of threat definition often devolves in undesirable practice upon some of the threat definer’s clients in the ranks of the net security provider’s foreign 

dependents. A prudent defense is one that is ready 

enough to meet threats that have matured or perhaps 

erupted less than was well anticipated in years previously. The extraordinary geopolitical, and hence 

geostrategic, scope of America’s foreign security provision is the source of exceptional, though certainly 

not historically unprecedented, anxiety. While identifiable potential dangers great and small need to be 

covered for potential military intervention, the United 

States has to be willing and able to attend productively to the structure of security in different regions 

around the world. The purpose of a prudent defense 

is to provide sufficient security for whatever may occur. Because precision in the definition of future threat 

is impossible, it is necessary to limit future ambition to 

the ability to cope with menaces by broad categories 

of risk and possible danger. Obviously, it has to follow that American military power needs to be notably 

mobile and friendly to jointness of enterprise.
44

Definition of Threat.

There are fortunately very few threats that all but 

demand to be so interpreted by their political owners. Russian modernization of its strategic nuclear 

forces and Chinese modernization and large-scale 

augmentation of its naval assets with obvious access-denial relevance spring to mind as unarguable 

contemporary examples of military developments 

abroad that plainly are intended to convey the idea 

of threat to the United States, at least to America’s 

long-standing interests. However, Americans should 

recognize that although their country is, in an important sense, simply another great state in strategic history’s lengthy procession of such, a combination of 

technology and historical circumstance has rendered 

the American role in international security truly exceptional. Imperial Athens was the proud possessor 

of distinctively unusual greatness in the 5th century 

B.C., but it discovered painfully that such greatness 

did not always translate into a usable superiority of 

power, e.g., in Egypt and later in Sicily.43 The contrast, but also some similarities, with the American 

experience from the 1960s until today almost beg for 

explicit notice. 

This is in no danger of becoming argument, let 

alone assertion, by claimed historical analogy. But it 

is notice of historical parallelism. A problem inherent 

in the very nature of empire, even of loose imperium 

such as that led by the contemporary United States, is 

that it proves impossible to know when to decide that 

the level of security currently attained can be judged 

sufficient. To go back to basics, one has to ask “Why 

might a threat be so designated?” Admittedly, there 

are some threats that lend themselves to metric analy-
45

sis, or at least appear to do so. However, even in a 

case where the strategic mathematics could be grim, 

it cannot be denied that the answer to the most characteristic of strategist’s questions, “So what?” may not 

be beyond all reasonable doubt. The point of note is 

that the real definition, especially with respect to the 

future, almost always is a zone for political deliberation and final judgment. In other words, definition of 

future threat can safely be assumed a matter allowing some discretion. Few threats are really self-defining. They do not emerge fully mature as to most 

likely consequences should they fail to be answered 

effectively today. The course of history, including 

history of a strategic kind, is a rat’s nest of potential 

causes and possible effects. Definition of future threat 

has to include effort to discern possible and probable 

second- and third-order effects. Given that often it is 

distinctly challenging even to anticipate with tolerable 

accuracy what a first-order effect will be, it should be 

plain enough to see that threat definition is very much 

an art and, moreover, is one for which the military 

intelligence officer needs to be well prepared by rich 

strategic historical exposure.

Historical Parallels Are the Norm, 

Not the Exception.

Our contemporary lives oblige us to be alert to 

change, as great and small challenges that are new 

to us personally require attention. It is all a matter of 

perspective. It can be difficult even to appreciate the 

probable fact of historical parallels that should be of 

educational merit for us. The issues of the day press 

upon us, each seemingly sufficiently novel as to stretch 

beyond feasibility of significant alleviation by the 
46

application of methods long understood, well tried, 

and by and large true enough. An important theme for 

this analysis has been the eternal relationship between 

continuity and change. The reason American defense 

professionals should read and study Thucydides’ admittedly challenging text is because his political and 

strategic world was not fundamentally different from 

ours.44 This means that his book should be regarded 

as a work of rare insight on a subject contemporary to 

the author that, in its essential features, has not really 

altered for nearly 2 1/2 thousand years. 

Of course, the differences between then and now 

are important, but they were changes that did not alter 

the nature of political relations among states by revolutionary impact or by cumulative adjustment over 

time. Indeed, it can be close to shocking to moral aspirations for our world, to be brought by facts to realize 

just how parallel the course of history often has been 

over millennia. The scope and depth of the historical 

parallelism typically is obscured from most of our 

notice by the necessary focus we have to place upon 

the challenges of today or upcoming tomorrow. Now 

inevitably has some novel features, novel in detail to 

us that is, though rarely so in prospective function. Because we have to be more or less genuinely expert in 

understanding our situation and its problems today, 

it is scarcely surprising that the true implications of 

the reality behind the concept of the great stream of 

time rarely achieve due recognition. Also, it is difficult to argue for the contemporary relevance of a text 

from ancient Greece, when the argument is advanced 

and sustained only by a small handful of scholars, 

whereas a wholly contemporary approach to our 

problem regularly is attended by a cast of hundreds or 

even thousands. 
47

Perhaps the greatest challenge to clarity of understanding lies in the fact that Thucydides offers education rather than training. Much as Clausewitz wrote 

a book designed to help prepare soldiers to be competent in making the practical decisions they would 

have to make in war, so Thucydides wrote a generally 

pitiless history of the realities of disaster and triumph, 

genius and folly, and everything in between. The 

grand continuity that we find in the strategic dimension to the great stream of time is attributed largely to 

the persistence of just three elements over millennia: 

(1) a human nature with motives that do not change; 

(2) our exclusivity of political organization(s) to provide security; and (3) the logic of strategy that is an 

enduring reality, even though its practice frequently 

is not conducted competently.

American Exceptionalism Is a Half-Truth.

The exceptionalist literature, both scholarly and 

popular, is right in dwelling upon the ways in which 

the United States differs from all other polities on 

Earth—up to a point, at least. Unfortunately, no matter how elevated the moral or cultural and political the 

exceptionalist claims are believed to be (in America), 

the unforgiving nature of international politics applies no less to the United States than it does to other, 

lesser, polities. The United States is truly exceptional 

in its size, in the sheer weight of domestic assets that 

it brings to the game of nations, and as a direct consequence in the power as influence that it can exercise. 

The definition of future threat that is our organizing 

challenge to analyze and explain here probably should 

be understood not to derive significantly from those 

domestic features of the American experiment, of 
48

which we Americans understandably tend to be most 

proud. It is plausible to argue that our public values 

(and often private personal ones, also) add spice to 

the flavor of our foreign policy. But it is rather more 

plausible to argue that our great power, understood 

as relative influence, will continue to be the principal 

reason for our particular role in world political affairs. 

The United States was the weightier side of an essentially bipolar balance all through the protracted 

Cold War, and we have remained preeminent, if now 

imminently challenged by China, for more than 2 decades thereafter. However, preeminence, even a relatively benign American form of hegemony, comes at 

a societal price that can be heavy. At the time of this 

writing, there is unmistakably convincing evidence 

that China is pursuing a generally prudent, cumulatively competitive course vis-à-vis the extant American-led order in East Asia and Asia–Pacific. The material and other evidence of competitive motivation 

is undeniable, and it will certainly continue to grow, 

provided domestic upheaval in China does not divert 

it. This Chinese competitive urge and long-term surge 

is all but obliged to be anti-American, simply because 

the United States remains the power still currently in 

the ascendant. 

On similar logic, the new Russia can hardly avoid 

regarding the United States as an adversary, since the 

(American) security promise (or guarantee?) in Article 

V of the North Atlantic Treaty Organization Treaty of 

1949 is the most essential element in the whole security pattern for (non-Russian) Eastern Europe. Russia 

is certain to provide ample evidence of threat in the 

future, but its relatively recent geopolitical losses and 

still worsening demographic situation in combination 

ought to damper risk-taking impulses in Moscow. 
49

However, this author finds little or no comfort in such 

a seemingly reasonable judgment. Current Russian 

geopolitical, geostrategic, and demographic weaknesses ought to have an effect on policy that discourages adventure, but as recent and current events have 

demonstrated, this is not so.

Threat need not always flow strictly from adversaries ready enough to take crisis to the brink and beyond if the dynamics of confrontation assume an all 

but organic activism that escapes careful control. Definition of future threat has to take account of the possibility of the need to face down foreign leaders who are 

erratically and episodically apparently risk-tolerant to 

a dangerous degree. As a general rule, I must register 

a negative view of American efforts, no matter how 

well intended, to remake distinctly alien foreign societies with their richly un-American cultures. Physical menace sourced in such cultures certainly should 

be defined as future threat, but measures to control 

it should not entail forceful and protracted American 

endeavor to spread our ideas and practices. 

My reason for this negative attitude is strictly 

pragmatic and is abundantly evidenced empirically. 

To be unmistakably explicit: the “American way” 

does not work well in many foreign cultures. If we 

have learned nothing else from the grim experiences 

in the 2000s in Afghanistan and Iraq, surely it must 

be this—it can never be sound strategy to attempt to 

achieve the literally impossible. The American imbroglios in Afghanistan and Iraq have been all too 

characteristic of mature hegemonic behavior, even 

misbehavior. Rephrased for the purpose of this monograph, it has been characteristic of very great powers, literally over the course of millennia, not to be 

sufficiently skilled in their statecraft and strategy as 
50

to know when and where to stop in the quest for an 

ever unreachable measure of national security. Threat 

definition is especially difficult at the present time because the United States plainly is well past the peak of 

its public’s willingness to bear new strategic burdens, 

all the while a near-peer competitor in the form of the 

People’s Republic of China assuredly is not going to 

be easily discouraged from opposing the existing security arrangements in Asia–Pacific. “Uneasy lies the 

head that wears the crown,” is a summative comment 

appropriate to the subject here.

Chance, Black Swans, and Unknown Unknowns.

As something akin to a codicil to this whole discussion, it is advisable to remind readers of the limits 

to prudent rationality in threat definition and subsequent consequential defense preparation. I must warn 

that we should not be wholly unprepared for developments that may emerge as if by chance or by a process that cannot be anticipated or predicted. The point 

most in need of clearest registration is that we have to 

be ready enough to cope with surprising events that 

could have effects very damaging to our security for 

decades to come. An improbable, but certainly possible, practical alignment of Chinese and Russian policy 

goals and strategy could pose a gigantic continentalist 

challenge that we would find difficult to meet. In addition, we must worry about the threat that would be 

posed to our conception of international order by the 

world’s first, but unlikely to be last, bilateral nuclear 

war. There will be many cases in the future, as there 

were in the past and are in the present (e.g., consider 

Gaza), of crises and wars in which the United States is 

not a principal participant; nonetheless, consideration 
51

of future threat definition cannot be indifferent to the 

incendiary potential of conflict that is almost structural to the basic dynamic functioning of the existing 

world order. 

It is well to remember that there has been and remains a legacy of U.S. leadership following World 

War II. This is American in design, sustenance, and 

still substantially American in practice, even though 

the U.S. role has been increasingly muted in recent 

years. Prominent among the themes in Thucydides 

is the danger that can lurk underappreciated in the 

obligations that a hegemonic power finds it has to its 

security clients. This is a perennial cost that is an inalienable consequence of international political leadership.45 The 21st may not be strictly another American century, but it is true to say that the most likely 

shape and structure of the international order yet to 

come is far from self-evident at present. This very 

uncertain international context makes a fundamental 

case for a prudent approach to threat definition and 

defense planning.

ENDNOTES 

1. Klaus Knorr, “Threat Perception,” in Klaus Knorr, ed., Historical Dimensions of National Security Problems, Lawrence, KS: University Press of Kansas, 1976, p. 116. This is the most insightful 

treatment of the concept and often arguable historical reality of 

threat known to this author. 

2. Bernard Brodie, “The Continuing Relevance of On War,” 

Carl von Clausewitz, On War, Michael Howard and Peter Paret, eds. and trans., Princeton, NJ: Princeton University Press, 

1976, p. 54.

3. I have endeavored to explore and explain the mystery of 

the future, and especially the more characteristic errors in “fu-
52

turology,” in my Strategy and Defence Planning: Meeting the Challenge of Uncertainty, Oxford, UK: Oxford University Press, 2014, 

esp. Chap. 1.

4. See Richard E. Neustadt and Ernest R. May, Thinking 

in Time: The Uses of History for Decision Makers, New York: Free 

Press, 1986.

5. I explored the problem of prudent defense planning in my 

Defense Planning for National Security: Navigation Aids for the Mystery Tour, Carlisle, PA: Strategic Studies Institute, U.S. Army War 

College, March 2014.

6. Thucydides, The Landmark Thucydides: A Comprehensive 

Guide to the Peloponnesian War, Robert B. Strassler, ed. and rev. 

trans., Richard Crawley (1876), New York: Free Press, 1996. 

The other widely available translation is that by Rex Warner, 

published by Penguin Books in 1954. It is a very good readable 

translation, but I must confess to a preference for the precision in 

Crawley’s high Victorian English (somewhat amended) over the 

looser modern usage in Warner.

7. Williamson Murray, “Thucydides: Theorist of War,” Naval 

War College Review, Vol. 66, No. 4, Autumn 2013, pp. 31–46.

8. Robert Gilpin, War and Change in World Politics, Cambridge, 

UK: Cambridge University Press, 1981, p. 7.

9. Ibid., p. 227.

10. I have sought to initiate debate on anachronism among 

students of strategy, but potential debaters have yet to come forward. See Colin S. Gray, The Strategy Bridge: Theory for Practice, 

Oxford, UK: Oxford University Press, 2010, Appendix C, “Conceptual ‘Hueys’ at Thermopylae? The Challenge of Strategic 

Anachronism,” pp. 267–277.

11. My thesis of there being an essential unity to all of strategic history is well supported in the outstanding essays in Williamson Murray and Richard Hart Sinnreich, eds., The Past as Prologue: 

The Importance of History to the Military Profession, Cambridge, MA: 

Cambridge University Press, 2006. Other books from the same 
53

intellectual stable also merit notice: Williamson Murray, War, 

Strategy, and Military Effectiveness, Cambridge, MA: Cambridge 

University Press, 2011; and Williamson Murray and Richard Hart 

Sinnreich, eds., Successful Strategy: Triumphing in War and Peace 

from Antiquity to the Present, Cambridge, MA: Cambridge University Press, 2014. Also well worthy of an honorable mention is John 

France, Perilous Glory: The Rise of Western Military Power, New Haven, CT: Yale University Press, 2011, a major work marred seriously only by the author’s near visceral disdain for some cultural 

explanation of strategic history.

12. I explain this process fully in my book, The Future of 

Strategy, Cambridge, UK: Polity Press, forthcoming in 2015.

13. See Harold D. Lasswell, Politics: Who Gets What, When, 

How? New York: Whittlesey House, 1936.

14. See Harry R. Yarger, Strategy and the National Security 

Professional: Strategic Thinking and Strategy Formulation in the 21st 

Century, Westport, CT: Praeger Security International, 2008.

15. By way of a rather sad example, General Stanley McChrystal’s exemplary military career propelled him into the higher elevations where policy and strategy have to connect in mutually 

supportive fashion, but his many successful efforts in Iraq and 

Afghanistan were largely undone in subsequent practice by the 

inability of the contemporary American strategy making system to develop a strategy that could meet its political challenges. 

Readers of McChrystal’s excellent memoirs can hardly help noticing that the author’s superb tactical and operational skill-sets 

do not appear to have been matched at all closely by like competence in strategic appreciation. See Stanley McChrystal, My 

Share of the Task: A Memoir, New York: Penguin, 2013. McChrystal 

plainly was aware, even acutely so, of the difficulty in translating 

tactical success into lasting strategic advantage. For example, he 

commented as follows on his special operations: “We executed 

missions; we did not wage campaign” (p. 181). A little further on, 

he observes that “[w]ithin a couple of months, by October [2005], 

we were able to see real evidence of the strategic impact I hoped 

would materialize when I explained it to the operators in Al Qaim 

that day” (p. 186). But, without an inclusive and single understanding of the political purpose of the campaign, it was not pos-
54

sible to devise a strategy that might enable the desired political 

path to be followed. Hew Strachan, “Strategy or Alibi? Obama, 

McChrystal and the Operational Level of War,” Survival, Vol. 52, 

No. 5, October–November 2010, pp. 157–182, is very much to the 

point. Generals will wage war tactically, they may succeed in performing operationally, but they cannot do strategy in the absence 

of political direction worthy of the name.

16. When actual combat performance reveals a large adverse 

tactical gap between the fighting power of our soldiers and that 

demonstrated by those of the enemy, operational artistry or strategic skill will not stage a rescue for you from acute and even dangerous embarrassment. As a recent biography of Dwight Eisenhower explained: “The fact is the green American troops were no 

match for the German veterans” [in Tunisia in February 1943]. 

Jean Edward Smith, Eisenhower in War and Peace, New York: Random House, 2012, p. 262. This judgment is supported amply in 

Rick Atkinson, An Army at Dawn: The War in North Africa, 1912–

1943, New York: Henry Holt, 2002, pp. 344–347.

17. Raymond Aron, Peace and War: A Theory of International 

Relations, New York: Doubleday, 1966, p. 285.

18. The concept and alleged empirical reality of America’s 

“unipolar moment” was given a hard time both by liberal scholars and by realists who were suitably fearful of the danger of an 

Athenian moment when “victory disease” all too easily could 

override prudential reasoning. For some appropriate views, see 

Charles Krauthammer, “The Unipolar Moment Revisited,” The 

National Interest, Vol. 70, 2002–03, pp. 5–17; and Christopher 

Layne, The Peace of Illusions: American Grand Strategy from 1940 to 

the Present, Ithaca, NY: Cornell University Press, 2006. For a brief 

overview of the “unipolar” 1990s, see Colin S. Gray, War, Peace 

and International Relations: An Introduction to Strategic History, 2nd 

Ed., Abingdon, UK: Routledge, 2012, pp. 248–250.

19. Thucydides leaves us no doubt that the principal threat to 

the security of Athenians flowed more from the distinctly flawed 

working of the empire’s democratic politics, especially its proclivity to promote crowd pleasing demagogues who were short of 

competence, high ethical standards, or both, than from vengeful 

Persians or strategically pedestrian Spartans. Political ruin tends 
55

to begin and end at home. Students of international relations need 

to remember this plain warning from the historical record.

20. I choose to define grand strategy as “the direction and 

use made of all the assets of a security community, including its 

military instrument, for the purposes of policy as decided by polities.” Gray, The Strategy Bridge, p. 263. This definition is, of course, 

perilously inclusive, possible even to a fault. An outstanding brief 

discussion of the concept of grand strategy, particularly in its relationship to history, has been provided by scholarly historian John 

Gooch. He advises that: 

[b]ecause grand strategy is the pursuit of national political 

objectives by harnessing all the means at the disposal of the 

state, politics lies at its core. This fact alone accounts for the 

longevity of Clausewitz, whose timeless observations still 

command the respect and admiration of most students of 

strategy, and for the obvious fervor with which his adherents stress the political side of strategy over the technical 

and technological.

 John Gooch, “History and the Nature of Strategy,” in Murray 

and Sinnreich, eds., The Past as Prologue, p. 143. There has been 

some rise in American interest in the concept of grand strategy, 

but this very large idea continues to defy attempts to secure a consensus as to its most proper meaning. Williamson Murray, Richard Hart Sinnreich, and James Lacey, eds., The Shaping of Grand 

Strategy: Policy, Diplomacy and War, Cambridge, MA: Cambridge 

University Press, 2011; and Charles Hill, Grand Strategies: Literature, Statecraft, and World Order, New Haven, CT: Yale University 

Press, 2010, are noteworthy attempts to provide historical and 

cultural contexts for the concept, while the most scholarly investigation to date is Lukas Milevski, “The Modern Evolution Grand 

Strategic Thought,” Ph.D. diss., Reading, UK: University of Reading, 2014, though Milevski, on balance, may be deemed more to 

have compounded controversy over meaning, rather than help 

solve it. However, his careful study is a most important advance 

toward our ability to find proper use of this vital idea.

21. This episode is too recent for there to be much impressive 

theoretical literature about it. My own distinctly humble efforts at 

explanation of the meaning of contemporary technical develop-
56

ments were summarized in a work and a monograph: Strategy 

for Chaos: Revolutions in Military Affairs and the Evidence of History, London, UK: Frank Cass, 2002; and Making Strategic Sense of 

Cyber: Why the Sky is Not Falling, Carlisle, PA: Strategic Studies 

Institute, U.S. Army War College, April 2013. Williamson Murray, “Thinking About Revolutions in Military Affairs,” Joint Force 

Quarterly, Vol. 16, Summer 1997, pp. 69–76, is a rare outstanding 

treatment of the revolution in military affairs (RMA) enthusiasm 

of the period. The problem with the digital revolution is that it 

has occurred, indeed is still occurring, during a quarter century 

blessedly bereft of great power war, meaning that technical and 

tactical advances have galloped on, leaving strategic understanding largely shrouded in mystery.

22. The proposition that politics/policy and strategy are more 

important than tactics and technology has become close to thematic in the writings of historian Williamson Murray. See his 

Military Adaptation in War: With Fear of Change, Cambridge, MA: 

Cambridge University Press, 2011; Murray, War and Military Effectiveness, Cambridge, MA: Cambridge University Press, 2011; and 

Murray and Sinnreich, eds., Successful Strategies, Cambridge, MA: 

Cambridge University Press, 2014.

23. Intellectual mastery of the subject of nuclear threat requires understanding of the somewhat rival theories and arguments advanced by both Thomas C. Schelling and Herman Kahn. 

See Thomas Schelling, The Strategy of Conflict, New York: Oxford 

University Press, 1963; Thomas Schelling, Arms and Influence, New 

Haven, CT: Yale University Press, 1966; Herman Kahn, On Thermonuclear War, Princeton, NJ: Princeton University Press, 1960; 

and Herman Kahn, Thinking About the Unthinkable, New York: 

Avon Books, 1962. The sharp contrast between Schelling and 

Kahn’s thinking on nuclear threat is an intellectual centerpiece to 

Keith B. Payne, The Great American Gamble: Deterrence Theory and 

Practice From the Cold War to the Twenty–First Century, Fairfax, VA: 

National Institute Press, 2008.

24. A careful set of historical case studies concluded that reputation for integrity toward commitments has not been the dominant force for credibility. A superior weight of evidence supports 

the proposition that political leaders are far more impressed by 

their assessment of the quality of current interest an opponent ap-
57

pears to have in a particular issue, rather than in that adversary’s 

past record of fidelity in promised action to support declared 

interests. See Daryl G. Press, Calculating Credibility: How Leaders Assess Military Threats, Ithaca, NY: Cornell University Press, 

2005. This is one of those modest insights from scholarship that 

can have immense practical significance. It is no exaggeration to 

claim that the whole theory of deterrence in strategy may need 

to be redrafted if Press is judged to have read history correctly. It 

should be needless to say that it is orthodox to believe that reputation tomorrow can be at risk to perception of irresolution and 

weakness today.

25. Although states and their societies have armed forces 

that reflect more than casually their social roots and sustaining 

influences, also it is true that war, indeed each particular war, is 

a whole phenomenon that more than somewhat evolves seemingly organically, changing the style and some of the practices of 

the competitive belligerents. My point is that despite the hostility 

involved, a war is a dynamic episode that adversaries share. To 

a meaningful degree, they must wage a single contest, and their 

means and methods are certain to share some common features. 

For a particularly persuasive explanation of this character of war, 

see Patrick Porter, Military Orientalism: Eastern War Through Western Eyes, London, UK: Hurst, 2009, pp. 65, 170, 191.

26. At long last, the ideas of adaptability and adaptation have 

begun to be recognized for the importance that they must have. 

See Murray, Military Adaptation in War.

27. See Colin S. Gray, “Strategic Thoughts for Defence 

Planners,” Survival, Vol. 52, No. 3, June–July 2010, pp. 36–38.

28. An outstanding and revealing recent report on command 

experience in American context is General Stanley McChrystal, 

My Share of the Task, New York: Penguin, January 2013.

29. Richard Ned Lebow and Barry S. Strauss, eds., Hegemonic 

Rivalry: From Thucydides to the Nuclear Age, Boulder, CO: Westview Press, 1991, aired some rival views of Thucydides’ relevance 

to our modern times, while a rather later assessment by David A. 

Welch at least was admirably explicit in to its message to scholars: “Why International Relations Theorists Should Stop Reading 
58

Thucydides,” Review of International Studies, Vol. 29, No. 3, July 

2003, pp. 301–319.

30. Thucydides, The Landmark Thucydides, p. 16.

31. The most helpful guide to the subject of this monograph 

is Michael Howard, The Lessons of History, New Haven, CT: Yale 

University Press, Chap. 1.

32. As Zara Steiner makes very clear indeed, the United States 

was quite heavily engaged in international relations during the 

1920s and 1930s, but by choice it was not really on the field of play 

that contained the elements we must include as being relevant in 

the category of strategic history. See the magisterial treatment of 

the interwar decades in her books: The Lights That Failed: European 

International History, 1919–1933, Oxford, UK: Oxford University 

Press, 2005; and The Triumph of the Dark: European International 

History, 1933–1939, Oxford, UK: Oxford University Press, 2011.

33. Knorr, “Threat Perception,” p. 112.

34. See Nassim Nicholas Taleb, The Black Swan: The Impact of 

the Highly Improbable, New York: Random House, 2007.

35. McChrystal provides an excellent participant’s view of 

recent history of the U.S. Army.

36. Thucydides’ core arguments on strategy are well summarized in Athanassios G. Platios and Constantinos Koliopoulos, 

Thucydides on Strategy: Grand Strategies in the Peloponnesian War 

and their Relevance Today, London, UK: Hurst, 2010. An essay helpfully contextual for the book by Platios and Koliopoulos is Paul A. 

Rahe, “Thucydides as Educator,” in Murray and Sinnreich, eds., 

The Past as Prologue, pp. 95–110.

37. Michael Howard advises that:

history, whatever its value in educating the judgement, 

teaches no ‘lessons,’ and the professional historians will be 

as skeptical of those who claim that it does as professional 

doctors are of their colleagues who peddle patent medicines 

guaranteeing instant cures. The past is infinitely various, 
59

an inexhaustible storehouse of events from which we can 

prove anything or its contrary. . . . historians may claim to 

teach lessons, and often they teach very wisely. But ‘history’ 

as such does not.

Lessons of History, p. 11.

38. I advance this claim on behalf of historical education in 

my book, Strategy and Defence Planning.

39. The concept of the historical parallel avoids the impossible difficulties with analogy, while being encouraging of potentially fruitful search for enlightening similarities in the structure 

of diverse historical episodes. I am pleased to acknowledge debts 

to Klaus Knorr and Michael Howard for my appreciation of the 

merit in this idea. Knorr, “Threat Perception”; Howard, The Lessons of History, Chap. 1.

40. See the following small gem of a book, General Sir Andrew 

Skeen, Lessons in Imperial Rule: Instructions for British Infantrymen 

on the Indian Frontier, (1932) London, UK: Frontline Books, 2008.

41. Donald Rumsfeld, Known and Unknown: A Memoir, New 

York: Sentinel, 2011, p. xiii.

42. Thucydides, A Comprehensive Guide to the Peloponnesian 

War, p. 43.

43. Ibid., pp. 56, 128.

44. No less an authority than General of the Army George 

Catlin Marshall told an audience at Princeton University on 

February 22, 1947, that he doubted:

whether a man can think with full wisdom and with deep 

convictions regarding certain of the basic international issues today who has not at least reviewed in his mind the 

period of the Peloponnesian War and the Fall of Athens.

Quoted in Paul A. Rahe, “Thucydides as Educator,” in Williamson Murray and Richard Hart Sinnreich, eds., The Past as 

Prologue, p. 99.
60

45. See Thucydides, A Comprehensive Guide to the Peloponnesian 

War, pp. 53–54. Because it rests largely on an historical narrative 

structure, Thucydides’ great book is not designed in the manner of our contemporary social science text books, with chapters 

discretely targeted to develop particular ideas or theories. As a 

consequence, one finds a particular phenomenon (e.g., alliance 

behavior and misbehavior) integrated into the whole of the narrative, which is to say in proper historical context. Consideration of 

alliance or client, relationships in Thucydides is assisted usefully 

by the following works: Donald Kagan, Thucydides: The Reinvention of History, New York: Viking, 2009; and Platios and Koliopoulos, Thucydides on Strategy. While Athens was a strategically giant 

ally, it was inevitably a greatly resented collector of security tribute, too. On balance, both then and now, it is a persisting reality of 

international politics that the dominant partner in a relationship 

of security dependency finds that it must adopt some local causes 

of concern, ambition, and anxiety in the interest of tolerable alliance relations. Small security-dependent clients are fully capable 

of manipulating a very great power into an imprudent commitment to provide assistance.
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