Zivilschutz
In the United States, the sheer power of nuclear weapons and the perceived likelihood of such an attack precipitated a greater response than had yet been required of civil defense. Civil defense, previously considered an important and commonsense step, became divisive and controversial in the charged atmosphere of the Cold War. In 1950, the National Security Resources Board created a 162-page document outlining a model civil defense structure for the U.S. Called the "Blue Book" by civil defense professionals in reference to its solid blue cover, it was the template for legislation and organization for the next 40 years.