Comment Re:Don't buy it! (Score 1) 65
Yes, there is much truth in that. (Though you discount the rapid advances in computational power just after the war. Even though the computational effort is "massive" that only spurred the various signals intelligence organisations to buy more computers).
However, as no-one thought the Enigma had been broken to the extent that it had, no-one put that much effort in to perfect crypto hygiene, not reusing or reordering rotors (the Germans famously got that completely wrong, thinking that the strength was increased by changing rotor order), etc.
So while a properly configured and expanded Enigma could have been the basis of a sound and secure means of communication, that wasn't how it was typically used.
I mean, even the Germans had somewhat proper cryptographic procedures, but since they didn't believe that their crypto could be broken, they developed a very lackadaisical attitude in practice. Not so the allies, where their own knowledge of the fallibility of such systems made them stress proper procedure at all times to a much greater degree.
(There's a famous example from Beurlings Gehimschreiber break in Sweden. We can surmise that there was an order that all messages should start with a random word, to avoid stereotypical cribs at the start of a message. All good and well so far. But then the order probably continued "for example Sonnenschein".
You guessed it. All of a sudden more than 95% or so of all messages started with the word "Sonnenschein". The odd bright young spark managed "Mondschein" and a jester put "Donaudampfschiffsfhartskapitaensmuetze". So, while the intention was good, in actual practice messages got easier to break after that...)