and cover" or more accurately, cover-and-then-duck advice without using those specific terms in its Six Survival Secrets For Atomic Attacks section. 1. Try To Get Shielded 2. Drop Flat On Ground Or Floor 3. Bury Your Face In Your Arms ("crook of your elbow"). The child-orientated film Duck and Cover was produced a year later by the Federal Civil Defense Administration in 1951. Education efforts on the effects of nuclear weapons proceeded with stops-and-starts in the US due to competing alternatives. In a once classified, 1950s era, US war game that looked at varying levels of war escalation, warning and pre-emptive attacks in the late 1950s early 1960s, it was estimated that approximately 27 million US citizens would have been saved with civil defense education. At the time however the cost of a full-scale civil defense program was regarded as lesser in effectiveness, in cost-benefit analysis than a ballistic missile defense (Nike Zeus) system, and as the Soviet adversary was believed to be rapidly increasing their nuclear stockpile, the efficacy of both would begin to enter a diminishing returns trend. When more became known about the cost and limitations of the Nike Zeus system, in the early 1960s the head of the department of defense determined once again that fallout shelters would save more Americans for far less money. The production of Duck and Cover in 1951 by the Federal Civil Defense Administration occurred during the height of the Korean War (1950–1953), and coincided with the first Desert Rock exercises in the Nevada desert which were designed to familiarize the US military with fighting alongside battlefield nuclear weapons, as it was feared that a resolution to the Korean War might need the theater of operations to first expand across the border into the People's Republic of China and require nuclear weapons to end it. The film was also produced at least one year before the first "hydrogen bomb" or megaton range explosive device was demonstrated to be possible, with test shot Ivy Mike in 1952. At least four years before the first true "hydrogen bomb" of the Soviet Union (USSR), the RDS-37, on November 22, 1955, which yielded 1.6 megatons. About 6 years before the first successful test launch of the world's first intercontinental ballistic missile (ICBM), the Soviet Union's R-7 in 1957, up until this time strategic bombers were not but one of the three strategic nuclear triad delivery