As a child visitor to the Imperial War Museum in London, I was fascinated by models of the first-world-war trench systems, and especially by a cutaway of an imitation tree from which a British officer with binoculars spied on the antics of the dastardly Hun. The British loved such artifices. One of their real-life originators was a painter well known to the Royal Academy named Solomon J Solomon. A man with influential connections, he secured royal patronage for his experiments in constructing artificial trees. Gardeners at Windsor helped chop down a willow that Solomon lovingly reconstructed around a portable steel shell. The artist wrote reverentially to Buckingham Palace: “The King's own trees will now, I hope, help and protect the men who will erect and make use of the armoured outposts.”

Solomon was made a colonel in the Royal Engineers, and travelled to France in 1916 to experiment with his creations. When he asked Sir Douglas Haig for a field to play in, the commander-in-chief responded: “The whole of Flanders is at your disposal.” Solomon's gadgets were not an unqualified success, but they delighted their inventor, as do most such forays into unconventional warfare by irregular warriors.

Nicholas Rankin is a former BBC correspondent who, two years ago, published a widely praised biography of George Steer, the Times journalist who broke the story of the 1937 bombing of Guernica. Rankin has now turned his attention to deception in the two world wars. His thesis is that the British possess a genius in this field, in which he includes camouflage, propaganda, intelligence and special forces.

Rankin's title is justified chiefly because Winston Churchill was a keen believer in deception. When, as First Lord of the Admiralty, he visited the fleet at Scapa Flow in 1939 and saw dummy warships at anchor, he immediately spotted a flaw: no seagulls. “You always find gulls above a living ship,” he told the admirals magisterially. “Keep refuse in the water day and night! Feed the gulls and fool the Germans.”

Rankin provides glimpses of the famous Double-Cross System, by which MI5 fed intelligence to Berlin throughout the war via fictitious spy networks in Britain; of “The Man Who Never Was”, where a tramp's body was deliberately jettisoned off the coast of Spain in April 1943 dressed as a Royal Marine officer, carrying papers suggesting that the allies planned to invade Greece, not Sicily; and of the dolls parachuted into Normandy in June 1944, to confuse the German D-Day defenders.

He tells the story of Major H Hesketh-Pritchard, a fanatical peacetime sportsman who developed sniping and fieldcraft techniques during the first world war, and of TE Lawrence and his Arab masquerades. The British were unimpressed when the enemy adopted similar practices.In 1915, the magazine War Illustrated captioned a picture of a captured sniper lavishly adorned with foliage: “The Turk, wily as are all Orientals, is quick to assimilate the ideas of his temporary masters.”

Two of the people who Rankin singles out for particular attention are Dudley Clarke and Sefton Delmer. Clarke was born in South Africa in 1899, and became a regular British officer in 1916. Always a theatrical enthusiast, in 1923 he was responsible for the gunners' display at the Royal Tournament. For this, he assembled a cast of 680 men, along with 37 guns, two elephants, two camels, 16 oxen, eight Sikhs and 14 huge Nigerians.

In the 1930s, Wavell, the British c-in-c in Palestine, got to know and like Clarke. In 1940, by now masterminding Britain's desert campaign, he demanded Clarke's services. Clarke stepped off the plane in Egypt disguised as an American journalist, in loud black-and-white plus fours, a check cap and sunglasses. He became the hero of A Force, charged with all forms of deception in Libya, and achieving

an extraordinary reputation as the architect of decoy tank units and dummy airfields full of planes, as well as subtler ruses involving intelligence and signals scams.

Clarke was acknowledged as an initiator of a whole school of strategic deceits, of which those that preceded and followed D-Day in June 1944 were the most famous and successful. Unfortunately, his military career was crippled by an extraordinary episode in Madrid in October 1941. He was arrested by Spanish police in the street, dressed and made up as a woman. The MI5 officer Guy Liddell wrote in his diary: “I am afraid that after his stay in Lisbon as a bogus journalist, he has got rather over-confident about his powers as a secret agent. It would be much better if these people confined themselves to their proper jobs.”

Delmer was born in Berlin to Australian parents, and became a renowned Daily Express correspondent among the Nazis. He spent most of the war beaming “black propaganda” to Germany under the auspices of the Political Warfare Executive, seeking to demoralise the enemy by telling them fiendishly plausible stories about the sex lives of the Nazi leadership and suchlike. As with so many such enterprises, it is hard to say how much this one damaged Hitler's cause, but it gave enormous pleasure to Delmer and his colleagues.

All of this is good rollicking fun, but the book becomes confused when the author injects reference to Tony Blair's 2002 “dodgy dossier” on WMD into his copy, and asserts apropos of nothing in particular that “the three-trillion-dollar war in Iraq has been a propaganda disaster for ‘the good guys'”. Rankin's book also suffers severely from a lack of focus. He often seems uncertain whether he is telling the story of the wars - for instance, devoting several pages to a description of the Gallipoli campaign - or illustrating the development of deception.

It is questionable, too, whether his initial thesis holds up to careful scrutiny. The history of warfare is full of attempts to deceive the enemy, from the wooden horse of Troy to the 1991 coalition campaign in Kuwait. The British in South Africa, for instance, thought the Boers shockingly unsporting because they insisted on lying down and firing from cover, rather than standing up like men to be shot at.

Rankin is a talented writer who will surely write good books that scatter their fire less recklessly than this one does. Deception in the world wars is a fascinating subject, which has been discussed with insight and rigour by such historians as Michael Howard and Thaddeus Holt. Rankin's romp over the course adds nothing to our knowledge, and only a chuckle or two to our amusement.

Churchill's Wizards by Nicholas Rankin
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