In 1951, the Chairman of the AEC strongly advocated the development of nuclear weapons for tactical purposes. "We could," he asserted, "use an atomic bomb today in a tactical way against enemy troops in the field, against military concentrations near battle areas and against other vital military targets without risk to our own troops." TUMBLER-SNAPPER was accordingly designed both to advance the development of effective nuclear weapons and to train troops in tactical nuclear warfare (9: 25). The series, like BUSTER-JANGLE, was originally planned as two separate testing programs: Operation TUMBLER, to be conducted at the NTS before 1 May 1952; and Operation SNAPPER, scheduled to begin at the NTS on 1 May 1952. Because the programs planned for the two series sometimes overlapped, they were combined into one operation, TUMBLER-SNAPPER (9: 26-28). The series consisted of two phases. The TUMBLER phase, of primary concern to the DOD, featured four weapons effects tests: CHARLIE, and DOG. ABLE, BAKER, These airdropped devices were detonated to collect informa- tion on the effect of the height of burst on overpressure. Shots CHARLIE and DOG were also part of the SNAPPER phase, of primary concern to the AEC and the Los Alamos National Laboratory. The other weapons development tests in the SNAPPER phase were EASY, FOX, GEORGE, and HOW. The primary purpose of these four tower shots was to gather information on nuclear phenomena and to improve the design of nuclear weapons (9: 1). ‘4.7.2 TUMBLER-SNAPPER Test Operations. About 7,350 of the estimated 8,700 DOD participants in Operation TUMBLER-SNAPPER took part in Exercise Desert Rock IV. The remaining DOD personnel assisted in scientific experiments, air support activities, or administrative and support activities at the NTS (9: 1). Exercise Desert Rock IV, an Army training program involving personnel from the armed services, included observer programs at Shots CHARLIE, DOG, FOX, and GEORGE and tactical maneuvers after Shots CHARLIE, DOG, and GEORGE. The tactical maneuvers were designed in part to provide realistic training for 9]