THE DECEIVERS

Allied Military Deception in the Second World War

By Thaddeus Holt

Scribner. 1,148 pp. $49.95

On April 30, 1943, the body of a British Royal Marine was found floating in the water near the southern port city of Huelva, Spain. Even more curious was the briefcase handcuffed to his wrist. Authorities notified the British naval attache the next day, and on May 2 the remains of poor Maj. William Martin, drowned at sea, were laid to rest. Soon after, the major's documents and personal effects were returned. And although certain envelopes among those effects appeared to be sealed, the British had assumed that local officials would pry them open. For if they did, they would find a letter from the Imperial General Staff to Field Marshal Harold R.L.G. Alexander mentioning an impending invasion of Sardinia and Greece. Such highly classified information then would be passed on to the Germans, who were anxiously awaiting the Allies' next move.

Of course, the Allies' next move was not against Sardinia or Greece, but rather Sicily. The documents discovered by the Spanish and passed to the Germans were fakes. Maj. Martin had not really been in the Royal Marines -- the body was that of a mentally disturbed man, Glyndwr Michael, who had killed himself in London by ingesting rat poison some three months earlier. Dubbed Operation Mincemeat, the entire affair was conducted by British intelligence as a cover plan for the invasion of Sicily. How it was conceived and carried out is but a fraction of "The Deceivers," Thaddeus Holt's monumental history of Allied military deception in World War II.

As the first nonofficial historian granted access to the records of American Joint Security Control at the Pentagon, Holt fully reveals Allied attempts to "mystify, mislead, and surprise" the enemy, while identifying the intelligence failures, the successes and the many operations whose decisiveness remains unclear even today. The level of detail is staggering. The list of colorful personalities is endless. But beneath the mountains of data (and more than 200 pages of appendices and references) lies the story of how American and British officers created deception and eventually mastered it.

By the time of Operation Mincemeat, the British had nearly perfected the art of deception. Besides the letter to Field Marshal Alexander, Maj. Martin had on his person theater ticket stubs and a photo of his supposed fiancee, Pam. There were love letters, correspondence from his father, a receipt for an engagement ring and even a photo ID (that of a look-alike).

"As early as May 12, ULTRA [the decrypting of German code] intercepts pointed unmistakably to the conclusion that the Germans had read the [phony] letter and had bought the 'story' hook, line, and sinker." Meanwhile, Gen. Alfred Jodl informed the German military attache in Rome that "You can forget about Sicily, we know it is Greece."

Not that deception operations always went so swimmingly. Late in 1940, British officials tried fooling the Italians into thinking that Somaliland in Eastern Africa was being targeted, thereby causing a shift in Axis units away from Libya, the real objective. The deception was so convincing, however, that instead of strengthening Somaliland, the duke of Aosta decided to concede it entirely and focus on his northern front -- where the British were preparing to advance. Calling this profound error the Camilla principle (named after the operation), Holt explains that "what you must focus on is not what you want the enemy to think but what you want him to do."

When British intelligence spread a rumor of a highly lethal Australian "K-Shell," reporters became extremely curious and demanded more information. But given only two options, either lying to the press or spilling the secret, officials opted to abandon the project, leading to the K-Shell principle: "Never conduct a deception with no clear object simply because you can do so."

Though British methods needed fine-tuning, they were better than "the burgeoning but helter-skelter development" of American deception. However, the uneven American performance did lead to advances in sonic deception and the formation of essential units such as the Navy Beach Jumpers, which created the illusion of a looming naval task force, and the 3103rd Signal Service Battalion, which gave an impression of advancing armored and infantry divisions. Indeed, the Americans made substantial progress in time for Bodyguard, the grand deception plan for 1944 meant to lead the Germans into believing that Norway and the Balkans were next to be invaded, not northern France. And as D-Day approached, the further aim was to keep the Third Reich focused on Calais as a landing site and not Normandy.

This was the height of Allied deception. Double agents reported on the movement of fictitious units; signal intelligence issued more than 13,000 phony messages; and, perhaps most audaciously, an actor disguised as Field Marshal Montgomery appeared in Gibraltar at the end of May, suggesting to the Abwehr (German intelligence) that a landing in France could not be imminent if Monty was away on travel. "Given the enormous stakes," writes Holt, "it was perhaps the most successful strategic deception of all time." The Germans believed that the Allies possessed more than 100 divisions when they had only about 50. Hitler himself was transfixed by an invasion of Norway, calling it "the zone of destiny of this war."

Allied deception operations against the Japanese, on the other hand, were less sophisticated, since the empire's intelligence system was, in Holt's words, "too incompetent to understand what was being told them, and stood too low in the estimation of the decisionmakers for it to have done much good if they had." Nevertheless, the Pacific was where the United States saw "the most elaborately executed American deception of the war," Operation Bluebird: the notional invasion of South China and Formosa while the true objective was Okinawa.

"The Deceivers" is no Tom Clancy novel, not with its dense, sometimes technical information about deception tactics involving techniques and devices now obsolete. Rather, Holt has provided us with a historical record. And this he does definitively. Holt also performs a service by making certain these fine men and women will not be forgotten. After all, there is no memorial dedicated to the deceivers -- unless you count that gravestone in Huelva, Spain, where even today you can read the inscription for a certain Maj. William Martin, "born 29th March 1907, died 24th April 1943, beloved son of John Glyndwr Martin and the late Antonia Martin, of Cardiff, Wales. Dulce et decorum est pro patria mori. R.I.P."