The Pentagon refused to allow the Allied field artillery use of the fuzes in 1944, although the United States Navy fired proximity-fuzed anti-aircraft shells during the July 1943 invasion of Sicily. After General Dwight D. Eisenhower demanded he be allowed to use the fuzes, 200,000 shells with VT fuzes or (code named "POZIT") were used in the Battle of the Bulge in December 1944. They made the Allied heavy artillery far more devastating, as all the shells now exploded just before hitting the ground. German divisions were caught out in open as they had felt safe from timed fire because it was thought that the bad weather would prevent accurate observation. U.S. General George S. Patton credited the introduction of proximity fuzes with saving Liege and stated that their use required a revision of the tactics of land warfare.