Groves's and Montague's: that nuclear weapons needed to be available in an emergency, and the men who had to use them in battle needed to have experience with their maintenance, storage and handling. Norris Bradbury, who had replaced Oppenheimer as the director of the Los Alamos Laboratory in December 1945, argued that rapid transfer could be accomplished by improved procedures and that the other difficulties could best be resolved by further development, mostly from the scientists. Forrestal and Carpenter took the matter up with Truman, who issued his decision on 21 July 1948: "I regard the continued control of all aspects of the atomic energy program, including research, development and the custody of atomic weapons as the proper functions of the civil authorities." With the outbreak of the Korean War in 1950, air transport resources were put under great strain, and it was decided to reduce the requirement for it by pre-positioning non-nuclear components at locations in Europe and the Pacific. That way, in an emergency, only the nuclear components would have to be flown out. In June, Truman ordered the transfer of 90 sets of non-nuclear Mark4 components to the AFSWP for training purposes. In December, he authorized the carriage of non-nuclear components on board the Midway-class carriers. In April 1951, the AEC released nine Mark4 weapons to the Air Force in case the Soviet Union intervened in the war in Korea. These were flown to Guam, where they were maintained by the Air Force special weapons unit there. Thus, at the end of 1951, there were 429 weapons in AEC custody and nine held by the Department of Defense. In the light of this, a new AEC-AFSWP agreement on "Responsibilities of Stockpile Operations" was drawn up in August 1951, but in December, the Joint Chiefs of Staff began a new push for weapons to be permanently assigned to the armed forces, so as to ensure a greater degree of flexibility and a higher state of readiness. On 20 June 1953, Eisenhower, now as president, approved the deployment of nuclear components in equal numbers to non-nuclear components, and the Atomic Energy Act of 1954 amended the sections of the old act that gave exclusive custody to the AEC. By 1959, the nuclear stockpile had grown to 12,305 weapons of which 3,968 were in AEC custody and the remaining 8,337 were held by the Department of Defense. The total yield