Bletchley Park codebreakers' contribution to WWII overstated, new book claims

Allied crpytographers at Bletchley Park broke Nazi codes during WWII.

(CNN)The contribution of famed codebreaking facility Bletchley Park to the Allied victory in World War II has been overstated, according to the author of an official history of British intelligence agency GCHQ.

Codebreakers at the GCHQ facility deciphered Nazi Germany's communications and were credited with turning the tide of the war, but John Ferris, whose book "Behind the Enigma" was published Tuesday, told CNN that the British public had created a myth around the facility that overstated its influence.
"I'm second to none in admiring Bletchley and the way it operates, but the key thing is intelligence never wins a war on its own," said Ferris. "It can't, you have to have force."
    Nazi Germany considered its "Enigma" codes unbreakable.
    Ferris believes that a myth has been built around the codebreaking operation at Bletchley Park.
    "For British people, 1940 has taken on greater and greater significance as time goes by," he said. "They see it almost as the moment when modern Britain was created."
    Bletchley became part of this founding myth with the release of details about the operation, which seemed to suggest it was the reason Britain won the war, added Ferris.
    The activities at Bletchley Park remained a secret for several years after the conflict.
    Some historians have argued that the success in cracking the Enigma codes shaved two years off the war, but Ferris believes it more likely made victo