Book excerpt: From the book's Foreword: In the early 1970s, the U.S. Army Center of Military History contracted with BDM Corporation for a history of U.S. efforts to counter Soviet air and missile threats during the Cold War. The resulting two-volume History of Strategic Air and Ballistic Missile Defense covers the years 1945-1972 when the strategic arms competition between the United States and the Soviet Union was at its height. The study was first published for limited distribution in 1975 and recently declassified with minimal redaction. These volumes address the passive and active defense strategies, technologies, and techniques adopted by both U.S. and Soviet defense planners. Much of their actions centered around three common questions: How might we be attacked? How shall we defend our country? What can technology do to solve the basic problems of defending against this new intercontinental threat?