Bubble Bursting (Alan Turing in America and Message stupidity [Wikipedia])
Alan Turing spent some quality time in America, meeting up with some of the brightest mathematics and physicists there such as Claude Shannon, Alonzo Church and von Neumann:
"From September 1936 to July 1938 he spent most of his time at the Institute for Advanced Study, Princeton, New Jersey, studying under Alonzo Church. In addition to his purely mathematical work, he studied cryptology and also built three of four stages of an electro-mechanical binary multiplier.[21] In June 1938 he obtained his PhD from Princeton; his dissertation (Systems of Logic Based on Ordinals) introduced the concept of ordinal logic and the notion of relative computing, where Turing machines are augmented with so-called oracles, allowing a study of problems that cannot be solved by a Turing machine."
Our messaging people were just as stupid as the Germans and caused our codes to be broken too. One example:
"The B-Dienst, created in the early 1930s, had broken the most widely used British Naval code by 1935. When War came in 1939, the B-Dienst specialists had broken into enough British Naval codes that the Germans knew the positions of all British warships. They had further successes in the early stages of the War; the British were slow to change their codes. The B-Dienst could regularly read the British and Allied Merchants Ships (BAMS) code, which proved valuable for U-Boat warfare in the early phases of the Battle of the Atlantic. In February 1942, the B-Dienst broke into the code used for communication with many of the Atlantic convoys."