World War Two Essay, Research Paper

German naval leaders generally remained confident in the Enigma system throughout the war. Nevertheless, the security of their codes and ciphers was periodically brought into question by those fighting on the warfronts. From the conning tower perspective, Allied naval and air power seemed increasingly overwhelming. In some cases, U-boat sailors were convinced that their codes and ciphers were compromised when Allied forces suddenly appeared in the remotest of locations in the vastness of the open sea. Complaining about their suspicions to the German navy strategists ashore, U-boat sailors were compelled to continue using the Enigma system despite their concerns. In response, German naval leaders periodically ordered minor changes in their communications and cipher protocols, hoping that these changes would sufficiently complicate the Enigma system. Nevertheless, as various components of the Enigma system fell into Allied hands, Anglo-American cryptanalysts cooperated to solve Enigma with relative consistency.

Allied Tanker Burning off Virginia Beach, Virginia, in the Summer of 1942,

U.S. Navy photograph in the collections of The Mariners’ Museum

Page Illustrating the Communication Circuit Group TRITON,

Courtesy of the National Security Agency Cryptologic Museum

Solving the Enigma system remains one of the great Allied triumphs of World War II. During periods when Allied cryptanalysts were unable to solve Enigma, U-boats caused great damage to Anglo-American commerce. For example, Allied cryptanalysts were largely unable to solve U-boat messages enciphered on the M4 Enigma during the Drumbeat crisis, widely known as the codebreaking “blackout” of 1942. Solving the encrypted text of German navy radio messages became more complex when the Germans introduced the fourth rotor. Moreover, German naval leaders intensified the campaign against Allied shipping by dispatching more U-boats to sea. As a result of increased U-boat radio traffic, German naval leaders created a new network known as TRITON. Sometimes used as a general reference to the M4 Enigma, TRITON was, in fact, a designation for one of the “code-circle” or “communication circuit” groups used by U-boat signalsmen.

Initially, Allied cryptanalysts adapted to the TRITON network after the Germans created it in October 1941. However, they were unable to compensate when the Germans simultaneously changed Enigma plug-rotor settings and introduced the M4 Enigma on a broad scale aboard U-boats in early 1942. Consequently, the U-boat TRITON network was largely inaccessible to Anglo-American cryptanalysts, and Allied losses increased especially in American coastal waters in the spring and summer of 1942. With losses mounting, Anglo-American leaders agreed to work together more closely to solve the Enigma system in order to safeguard Allied shipping with intelligence