You claimed it was clear that Enigma would have been decoded, despite the fact that in eleven years of trying only one man had managed to come up with the key to cracking it so it is pure unsupported speculation to make your claim when the evidence is that the opposite is true. Unless you didn't mean that it is clear it would have been cracked within the 40s and meant in more general terms - I imagine it would have been defeated at some point in the last twenty or so years with the aid of computers. But a puzzle that defeated all but one person for eleven years to be then cracked by someone else within a 5-10 year period? Pure speculation I'm afraid.



The Eastern Front was of massive importance but of course information from Enigma was important to it - helping aid convoys carrying food and equipment convoys get through, aiding in the Atlantic theatre and in Africa (the latter two being vital in shutting Germany off from the outside world, preventing vital supplies, not least oil). The cracking of Enigma was a vital part of the Allied war effort and underpinned all the theatres of war, including the Pacific (where the Japanese used an encryption machine based on Enigma).

To quote Winston Churchill - "It was thanks to Ultra that we won the war" or Eisenhowerit was "decisive" in the eventual Allied victory in WWII.