what was the main weakness of the enigma machine
Cryptanalysis of the Enigma A major weakness of the system, however, was that no letter could be enciphered to itself. This meant that some possible solutions could quickly be eliminated because of the same letter appearing in the same place in both the ciphertext and the putative piece of plaintext. Comparing the possible plaintext Keine besonderen Ereignisse (literally, "no special occurrences"â€”perhaps better translated as "nothing to report"), with a section of ciphertext, might produce the following:
Zimmermann Telegram The Zimmermann Telegram (or Zimmermann Note or Zimmerman Cable) was a secret diplomatic communication issued from the German Foreign Office in January 1917 that proposed a military alliance between Germany and Mexico in the prior event of the United States entering World War I against Germany. Mexico would recover Texas, Arizona, and New Mexico. The proposal was intercepted and decoded by British intelligence. Revelation of the contents enraged American public opinion, especially after the German Foreign Secretary Arthur Zimmermann publicly admitted the telegram was genuine on March 3, and helped generate support for the United States declaration of war on Germany in April.[1] The decryption was described as the most significant intelligence triumph for Britain during World War I,[2] and one of the earliest occasions on which a piece of signal intelligence influenced world events.[3]