Every single time they used intercepted intelligence to their benefit, they made sure to leave false trails of other ways they could've known so the Germans wouldn't suspect.

I would expect the NSA could hide it well.

https://en.wikipedia.org/wiki/Coventry_Blitz#Coventry_and_Ul...

So I've read everything of his at least three times. And I'm waiting. Anyone know if something's immanent?

https://www.amazon.com/Rise-Fall-D-O-D-O-Novel/dp/0062409166...

Academia is much more advanced now; all the tools we have for reasoning about our cryptography were developed in academia, with no evidence that the NSA has shown any interest in that kind of stuff. (In fact the NSA has expressed disdain for academic cryptography).

[1] http://www.nature.com/naturejobs/science/articles/10.1038/35...

Besides, expecting a widely used and deployed cryptosystem to be uncompromised for years is absurd. They should have assumed it would be broken, and developed regular replacements.

There must have been a lot of people who had suspicions.

But consider: for many years, US citizens who talked about ECHELON were considered crazies. Later, Bush's enormous surveillance expansion was mostly denied or dismissed. The 2016 Russian hacks of the DNC and the propaganda machine were brought up on national television during the debates. Yet there was denial, dismissal, and very little concern.

Without a plan for responding or reacting, denial is a very appealing way to deal with upsetting news. The Germans and the Japanese who were in a position to suspect that their communications had been compromised were also embedded in a totalitarian military chain of command, more focused on preserving the relative power of the people at the top than anything else. Questioning the efficacy of the system is easily cast as disloyalty. What could anyone do?

If the British could not organize a parallel construction they simply let it go. They knew the plan for Crete invasion but they could not create a story on how they learned it so they preferred to lose naval control of the large part of the eastern Mediterranean sea. [0]

[0] https://www.amazon.com/Churchill-Secret-Service-David-Staffo...

1. the allies had enormous numbers of sub killers 2. the allies were incredibly lucky 3. Enigma was broken

Waiting for proof before acting is not a sensible decision.

(Even in WW1, the aviators regularly changed their codes used. They knew they were only good for a few days each.)

Who do you tell? And who is the guy that going to go to Hitler to tell him that their unbreakable system is broken?

BTW, my reading books about it suggests that one was not executed in the military for questioning orders. One reason the German military was so effective is much discretion was allowed by underlings, as well as listening to them.

I don't recall anything about the Germans doing the same thing.

The enigma had a new encryption code for everyday distributed on paper and torn off and destroyed once used. The were different codes and machines used in different branches of the army/navy and the system was updated through the war.

The British didn't get to see the machines or it's method for many years. There were 159 quintillion possible keys and even a 1 million guesses/second it would take 5 million years to guess a code - and don't forget they changed everyday. Also, remember there were no computers to do this, let alone one that that could even remotely approach 1 million operations a second.

So you ought to able to see at the time people were pretty confident it couldn't be broken, and if they hadn't made some mistake in it's use e.g. distributing weather reports, it might have not been.

We are arguably much more complacent than they were vs. their time. It was only recently that perfect forward security became a thing in HTTPS for example (i.e. different key for each connection).

I mean, it's not like they could even go read the Wikipedia piece on the German tank serial numbers info leak. Might have been a feature of a certain seminal strategy game - "you have defeated A[213 of 330]" ;-)

"retrieved a working Enigma machine along with the documents and code keys for three months. Not surprisingly, U-Bootwaffe fortunes declined in the following months, and from that point on Doenitz remained in doubt about the Enigma cyphers his boats were using. But the experts reassured him over and over again that they were sound, and so he retained them until the end of the war."