Why didn’t Friedman tell Byrne straight that his idea had no merit?

Byrne demonstrated an early model to Friedman in 1922 when the latter was chief cryptanalyst in the War Department. We can safely assume that Friedman knew exactly how the system worked. At the same time Friedman was studying working rotor machines and so he knew the capabilities of existing and of developing equipment.

If Byrne’s principle had no merit, as Friedman later maintained in 1954, why didn’t Friedman say so in 1922 and also why didn’t he tell Byrne not to bother to send an improved model? Was there an ethic that in the cloak and dagger world of Cryptology you never revealed anything to a civilian? Possibly.

Perhaps in the technology of the 1920’s Chaocipher did have merit and that is why Friedman didn’t damn it. But then you would have expected Friedman to actively pursue it – which he clearly didn’t.

 The likelihood in my mind is that in 1922 Friedman was told by a superior to humour a person of some influence who had a madcap idea. And Friedman did just that.

Once again in 1942 Byrne was asking Friedman to assess Chaocipher and once again Friedman was fobbing him off – this time with the request for a depth of messages. I see here the bureaucratic process at work. Friedman wasn’t interested (as witness his scribbled note to Lt. Hiser) but rather than be blunt about it he follows normal procedures and hopes the nuisance will go away -- which in the event it does!

Finally in 1954, when once again Byrne is taxing Friedman to acknowledge the merits of Chaocipher, Friedman has had enough. He tells Byrne to forget Chaocipher and focus on other things. That, as far as we know, is the last chapter on this topic in Byrne's lifetime.