PrimeWire

that wasnt really the problem .. the machine was invented in 1923 and freely commercially available for keeping industrial secrets .. capturing code books for the code of the day would have been more useful, but wouldnt last more than the expected length of a sub’s mission .. the real trick was the british invention of electronic computers, that could decode the signal fast enuf for the info to be useful .. but even then if they had taken too much advantage of the ability to listen in, they would have made it obvious the ratzi comms were broken, and the ratzis would have found some other way to encrypt comms .. so in many cases they had no choice but to let the subs have their way, to keep thier cards close to thier chest as it were .. the story that capturing an enigma machine was critical, was pushed for a very long time because the real code breaking methods were under the official secrets act for 50 years after the war