Churchill's Wizards, by Nicholas Rankin

When British troops in Afghanistan delivered a hydroelectric turbine to a power station under the noses of the Taliban, they won more adulation in the media for outwitting the Islamists than they ever received for blowing them to pieces. Perhaps this was because, as the former US Ambassador Raymond Seitz once said: "The British prize few things so much as a good performance." Called upon from an early age to seem open and good humoured while hiding their true feelings, the British know the value of showmanship. But it could also be because they are shysters. Such a tiny island would never have been able to rule a quarter of the globe with minimal personnel were it not for a talent to deceive. Whatever is the root of our national character, Nicholas Rankin's new book shows that it is clearly well suited to misdirection in wartime.

The earliest "wizards" of the title, active during the First World War, were not conmen or even boffins, but painters. These were the men and women who developed camouflage. They were trained in art school portraiture and theatre set design and led by a Royal Academician, Solomon J Solomon, whom Douglas Haig made up from a private to a lieutenant-colonel practically overnight. By contrast, a Frenchman was the first to invent the now ubiquitous camouflage fish netting, only to have his country's authorities reject it as having "no practical application" a few weeks before the war broke out.

Solomon's staff took their inspiration from the countershading on animals' bodies. For example, a lizard's markings have the effect of flattening his body against the ground and obscuring him from aerial predators. The same principles could be used to hide field guns and vehicles from aircraft.

Later there was also a role for writers and comedians. In May 1940, Dennis Wheatley, the famous author of novels about satanists, submitted a 7,000-word paper to MI5 on resisting a German invasion. He included a plan to set oil slicks alight that would roast the Germans in their landing craft. The RAF subsequently dropped copies of the Short Invasion Phrasebook on occupied France with useful translations of "The water is on fire" and "The boat is sinking" and helpful verb tables including "I burn / you burn / he burns / the SS Captain is burning quite nicely." It in fact proved impossible to set fire to the sea, but many Germans believed the tales of hideously burned soldiers washing up on beaches. Just in case, another rumour was put out that the British had imported 200 man-eating sharks from Australia and set them loose in the English Channel.

The book doesn't always live up to its subtitle. For example, the chapter titled "Deception in the Dardanelles" is almost a straightforward retelling of the Gallipoli campaign with a couple of anecdotes about Turks dressed up as bushes thrown in. A section on the great Daily Express correspondent Sefton Delmer is mostly about him hobnobbing with the Nazi elite in the pre-war years and having his pet parrot crap down Herman Goering's dinner jacket. There is also a good retelling of the Dunkirk story and a section on the Home Guard, but these tangents are always entertaining.

The most compelling stories concern the efforts of the true criminals among our armed forces. TE Lawrence described Richard Meinertzhagen as "so possessed by his convictions that he was willing to harness evil to the chariot of good". This is one way to describe a man who once made to shake hands with a Kenyan chief protesting about imperialist abuses and instead shot him dead with a pistol. He also beat one of his grooms to death with a polo mallet. Meinertzhagen thought the sexual abuse he had suffered at prep school gave him the excuse to commit any deed, so a career in intelligence suited him perfectly. It gave him pleasure to send a suspected spy a banknote and a thank you letter which he arranged to be intercepted so that the Germans would shoot the man for him. After the war he became a renowned ornithologist, with a large collection of bird skins stolen from other collectors.

Britain's military disasters have often been put down to an amateurish belief in sportsmanship and fair play. On the strength of this material, that entire characterisation seems like merely another ruse.