Electronics

General George S. Patton, the legendary commander of World War II, became an astute consumer of communications intelligence (COMINT); he learned its worth in the drive across Western Europe after D-Day and used it well. For example, in mid-August 1944, while Patton’s Third Army was located near the French city of Le Mans, the general and about 40 of his officers attended daily intelligence briefings. Here they would hear regular briefings by the G-2 (Intelligence) and G-3 (Operations), situation reports, and a news report from radio broadcasts. Following each meeting, all but seven officers were dismissed, and the rest stayed for a briefing on the enemy situation as seen in COMINT. This source proved valuable for the Third Army: ULTRA (the codeword assigned to COMINT derived from decryption of high-level German ciphers) material alone predicted a drive by five German Panzer divisions against the Third Army at Avaranches. In another instance, when Third Army headquarters moved near Chalons, an ULTRA message arrived at 0100 hours showing the German order for an attack at 0300. Patton had described the U.S. troops in the attack areas as spread out as “thin as the skin on an egg.” He found means to alert the defending divisions without jeopardizing the security of ULTRA, and the German attack was repulsed.

One member of Patton’s staff wrote about the value of ULTRA to Patton’s army stating that, “An army has never moved as fast and as far as the Third Army in its drive across France, and ULTRA was invaluable every mile of the way.”

NSA, Center for Cryptologic History, https://www.nsa.gov/about/cryptologic-heritage/historical-figures-publications/publications/misc/assets/files/50th_anniversary.pdf