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 systems of the modern era but the sole intercontinental nuclear weapon delivery system capable of reaching the US from the Soviet Union and vice versa
Ivy Mike
Ivy Mike
Duck and Cover (film)