jul 9, 1941 - Turing cracks the Enigma code

Description:

Alan Turing and his associates at Bletchley Park were able to crack the German encryption based off of work done by the Poles just before German invasion. For the rest of the war, Allies were able to read every German military correspondence, giving them warning of impending attacks and airstrikes as soon as the Germans decided on them. In order to ensure that they would keep this advantage, British high command deliberately allowed attacks to take place, sacrificing the lives of civilians and soldiers, unless they had a separate source to which they could attribute the knowledge.