Thinking About Deception

Fred Feer

Republished with the permission of the author.

5 August 2004

This brief paper discusses the most often asked questions about military deception.

  • What is it?

  • Why do it?

  • How do you measure its impact, or, how do you calculate its contribution to winning?

  • Can you rely on it?

What is Deception?

The answer to the first question is misleadingly simple. The official definition is:

deception — Those measures designed to mislead the enemy by manipulation, distortion, or falsification of evidence to induce the enemy to react in a manner prejudicial to the enemy’s interests. (JCS Publication 1, as amended March 2004)

It is misleading because it is narrowly drawn. To carry off a deception operation against a real enemy, one has to look further down the list of definitions, where you’ll find:

  • deception action — A collection of related deception events that form a major component of a deception operation. (JP 3-58)

  • deception concept — The deception course of action forwarded to the Chairman of the Joint Chiefs of Staff for review as part of the CINC’s strategic concept. (JP 3-58)

  • deception course of action — A deception scheme developed during the estimate process in sufficient detail to permit decisionmaking. At a minimum, a deception course of action will identify the deception objective, the deception target, the desired perception, the deception story, and tentative deception means. (JP 3-58)

  • deception event — A deception means executed at a specific time and location in support of a deception operation. (JP 3-58)

  • deception means — Methods, resources, and techniques that can be used to convey information to the deception target. There are three categories of deception means:
    a. physical means— Activities and resources used to convey or deny selected information to a foreign power. (Examples include military operations, including exercises, reconnaissance, training activities, and movement of forces; the use of dummy equipment and devices; tactics; bases, logistic actions, stockpiles, and repair activity; and test and evaluation activities.)
    b. technical means — Military materiel resources and their associated operating techniques used to convey or deny selected information to a foreign power through the deliberate radiation, re-radiation, alteration, absorption, or reflection of energy; the emission or suppression of chemical or biological odors; and the emission or suppression of nuclear particles.
    c. administrative means — Resources, methods, and techniques to convey or deny oral, pictorial, documentary, or other physical evidence to a foreign power. (JP 3-58)

  • deception objective — The desired result of a deception operation expressed in terms of what the adversary is to do or not to do at the critical time and/or location. (JP 3-58)

  • deception story — A scenario that outlines the friendly actions that will be portrayed to cause the deception target to adopt the desired perception. (JP 3-58)

  • deception target — The adversary decisionmaker with the authority to make the decision that will achieve the deception objective. (JP 3-58)

Beyond this nest of definitions one would find dozens of places where the word “deception” appears in the definitions of other terms or pointed to as an activity correlated with other activities such as “Defensive Information Operations” or “Command and Control Warfare.”

There is, however, a simple, action-oriented way to think about the what and the why of deception:

Everything done to manipulate the behavior of the other side, without their knowledge of the friendly intent, for the purpose of achieving and exploiting an advantage is deception. The “what” of deception is the manipulation of behavior. The “why” is to exploit the advantage achieved.

What point is there in deceiving an adversary if not to exploit the result? The object is not to fool the adversary, it is to exploit an advantage gained by inducing predictability in him, i.e., causing him to cooperate to our advantage.

The difference between the target and friendly intent is critical in terms of the distinction between deception and coercion. One could force changes in behavior on a target that the friendly side might exploit. This would not be deception, however, because the target would have no choice. It would have behaved as it did because of coercion and its knowledge of friendly intent, or lack of it, would have made little to no difference.

Concealment of the intent behind friendly actions is essential to concepts of deception because our manipulations would not achieve their objective if, by virtue of the other side’s knowledge of friendly intent, the target could refuse to act as we planned.

The relation between intelligence and deception is complex. Clearly the better our intelligence on the adversary’s intentions and capabilities the better we will understand how to induce the desired behavior in him. But it is also true that the more we rely on intelligence the greater the danger that we will ourselves be deceived. Bear this warning always in mind:

“As long as the enemy has a good intelligence service and pays attention to what it says, it will be possible to fool him again and again.” 1/

Geoffrey Barkas, the British officer in charge of many of the highly successful deceptions that beat Rommel in North Africa in 1942, had this insight after seeing the Germans capture a dummy oil port he had built and thinking that the Germans would never be fooled again after seeing what the British had been able to accomplish.

It is the search for information and the acting on it that creates a vulnerability. Without intelligence you could blunder, but you could not be deceived.

Why do Deception?

There are many reasons but they all come down to something Napoleon said:

“Battle should only be offered when there is no other turn of fortune to be hoped for, as from its nature the fate of a battle is always dubious.” 2/

Therefore one seeks every advantage possible.

What Napoleon was saying is what we mean here by saying that the impact of deception comes from one-sidedly reducing the level of uncertainty that afflicts all competitive relations. The deceptive techniques that are used, whether head fakes in basketball or option plays in football or honeynets in cyberspace are all intended to decrease one side’s—our side’s—level of uncertainty by getting our adversary to cooperate against his own interest.

The number of ways that can be accomplished is as varied as the people involved and the tools they use. Seeing how the available resources can be used for deceptive purposes requires imagination as much as anything else. It may be harder to see the analogies between the physical world and the cyber-world of networks and computer software, but the objective is the same whether what is involved is a feint with a brigade of tanks or a decoy network containing a file of false information. It is to get the adversary to respond in one way while we take advantage in another.

Designing and executing deception requires people, time, resources and effort. Resources are never sufficient to do all the things one might want to do. If combat outcomes are uncertain at best, why take risks for deception’s sake? Why not, simply overwhelm the enemy?

On one level the answer is simply that we do not have infinite resources and cannot always and everywhere overwhelm an adversary. On another level, however, commanders have an obligation to conserve resources both for humanitarian reasons but also because resources that may be abundant today may no longer be so tomorrow.

Sun Tzu, the great Chinese philosopher of war was very sensitive to this. He said, “All warfare is based on deception.” But many of his wise sayings praise the general who is able to accomplish missions at low cost in lives and treasure.

“One hundred victories in one hundred battles is not the most skillful. Subduing the other’s military without battle is the most skillful.” 3/

How Can You Measure Its Value?

Saving one’s own resources and causing the adversary to waste his seems a simple way to measure the value of deception. Setting up a honeypot would enable you to measure how long an adversary spent in one attempt to penetrate a network. But, of what value is that to the friendly side? What difference will X number of minutes of wasted adversary time make to an outcome desired by our side?

In the physical world it may be easier, at least, to conceptualize casualties not suffered, materiel not expended or bombs wasted on non-targets. But what is the cyberspace analog to these?

Perhaps hours of uninterrupted availability of networks. Hours of availability to friendly networks denied to an adversary? Hours of uninterrupted maintenance of rapid message dissemination? Number of dummy or doctored files downloaded by an adversary? All these may be worthwhile in particular circumstances. But how do these quantitative measures translate into qualitative successes?

Our preferred definition cited above puts exploitation of advantage at the center of deception and why we do it. It is well to waste an adversary’s time, but the question is, “What advantage do we enjoy as a result of the time gained?”

The impact of deception has to depend on whether the exploitation planned achieved the desired outcome. The extent to which the adversary behaved as we wished and the extent to which the advantage exploited achieved our aim, is the extent to which the deception was successful.

Risk of Failure

Deception may fail for many reasons along the chain of events that must occur from original idea to final outcome—just as every operation may fail for many reasons having to do with our forces or the adversary’s forces, the forces of nature or the laws of probability..

To list a few may be instructive:

  • We may fail to get our story to the adversary thereby failing to influence him.

  • He may misinterpret the information we provide him thereby behaving ways we may be unable to exploit.

  • We may fail to anticipate all the adversary’s potential courses of action.

British General Wavell and his deception chief Brigadier Dudley Clarke learned a valuable and highly relevant lesson early in World War II while they were fighting the Italian forces in Abyssinia [Ethiopia]. Wavell was planning an attack on the north flank so he feigned an attack on the south to draw reserves away from the north.

Unfortunately the Italians were not privy to his plans because they withdrew from the south and reinforced the north. Evidently the Italians had their own ideas about the relative importance of the two flanks.

From this experience Clarke drew a lesson still relevant. Deception plans start with this question,

“What do you want the enemy to do? Never, ‘What do you want the enemy to think?’” (Italics in the original.) 4/

  • We may fail to execute the deceptive operation competently. Competence is always desirable; never more so than when executing a deception.

  • We may fail to prepare the exploitation adequately.

Even a great deception success can have ambiguous results. The D-Day landings at Normandy in June 1944 are a case in point. The story of the deception operations preceding D-Day have been the subject of histories, movies, television documentaries and personal memoirs. Thousands of people labored over literally half the globe to plan and execute deceptions to divert German forces and prevent the Germans learning the exact day and place for the main landings—with apparent success.

But it is not clear that the success of those deceptions deserves the main credit for the success of the landings themselves. It can be argued—I would—that the single most critical decision leading to the success on 6 June 1944 was the decision to go ahead with the landings despite the bad weather. In addition to the weather, Allied commanders feared that a month-long delay to the next favorable window of tides, day- and moon-light would give the Germans time to penetrate the secret.

Because of their weather prediction the Germans assessed that the allies would not land, at least, for another several days. Their analysis of previous allied amphibious operations had given the Germans high confidence that they understood the allies’ criteria and their best weather prediction was that the criteria would not be met during the 6 June window.

But their weather prediction was wrong. It missed a two-day break in the weather that was coming from the northeast and was due to arrive at the Normandy area early on 6 June. Because of that gap in their weather intelligence the Germans were not at a the highest state of readiness that good weather would have dictated. The German commander, Rommel, was at home in Stuttgart for his wife’s birthday. Much of the senior German staff were away from their headquarters for a war game.

The German weather prediction was off because the US Coast Guard and Navy had uprooted German meteorological stations in Greenland and Iceland early in the war. At the time of the landings in June 1944 German weather reporting was confined to reporting from 2-3 U-boats in the North Atlantic. These were inadequate for accurate prediction of weather in western Europe. 5/

Does that mean the effort to deceive the Germans was wasted or unnecessary? By no means. The war required every effort and resource—if resources were available no possible effort to harm or deceive the enemy was refused. As Churchill said,

“In war-time truth is so precious that she should always be attended by a bodyguard of lies.” 6/


  1. Deception is about influencing adversary behavior in order to permit the friendly side to gain and exploit an advantage.

  2. The outcomes of deception operations are not assured. The adversary is an intelligent, adaptive, motivated human being. Contingencies must always be provided for.

  3. It is about manipulating behavior. Falsity, tricks and fooling people are tools and tactics. They are not the deception itself, The deception itself is the predictable, exploitable behavior of the adversary.

  4. The payoff to success may be great, but the payoff must be related to the intended exploitation and the achievement of the operational objective.

  5. If the exploitation is not fully planned and resourced, it may be better to forego it.


1 Barkas, G. The Camouflage Story. London: Cassell and Company Ltd;1952. Pp. 160-163.
2 Markham, F. Napoleon. New York and Scarborough, Ontario; 1963. p. 183.
3 Sun Tzu. The Art of War: A New Translation by the Denma Translation Group. Boston: Shambhala Publications, Inc.; 2001. Pp. 84 and 140 ff.
4 Mure, D. Master of Deception: Tangled Webs in London and the Middle East. London: William Kimber; 1980. P. 274.
5 Hinsley, F.H., et al. British Intelligence in the Second World War, vol. 2, Annex 7: German Meterological Operations in the Arctic, 1940-1941. New York: Cambridge University Press; 1981. Pp. 677-678 and vol. 3, p.125.
6 Cave-Brown, A. Bodyguard of Lies. New York: Harper & Row; 1975. P. 11.