While the Enigma Machine is truly fascinating, we largely only know about it because it failed. Meanwhile, the Allies had multiple encryption technologies fiel

While the Enigma Machine is truly fascinating, we largely only know about it because it failed. Meanwhile, the Allies had multiple encryption technologies fielded during the war that were far superior: https://en.wikipedia.org/wiki/SIGABA https://en.wikipedia.org/wiki/SIGABA https://en.wikipedia.org/wiki/SIGSALY https://en.wikipedia.org/wiki/SIGSALY https://en.wikipedia.org/wiki/SIGTOT https://en.wikipedia.org/wiki/SIGTOT But that's only part of the story - the allies were far more robust operationally. The Nazis were terrible at intelligence and counterintelligence (something to do with the subtlety required). And because they didn't take spying or intelligence seriously, they never "pentested" their own processes very well. They were fairly happy enough to create the Enigma machine and use it everywhere. Meanwhile, the allies were much more careful about what sort of encryption was used in each circumstance, and much more cautious about how much information (even encrypted) they made available for their enemy to intercept. If you really want to get into the details of how and why the Enigma was a failure, I strongly recommend Seizing the Enigma by David Kahn. It does an excellent job of combining the technical details of the Enigma codebreaking with the overall story of naval intelligence.