Since the dawn of the nuclear age, and especially since nuclear weaponry was wedded to ballistic means of delivery across intercontinental ranges, a major (some would agree the major) goal has been the avoidance of strategic nuclear war between the United States and the Soviet Union.
Snow, Donald M.
"Realistic Self-Deterrence: An Alternative View of Nuclear Dynamics,"
Naval War College Review: Vol. 39
, Article 7.
Available at: http://digital-commons.usnwc.edu/nwc-review/vol39/iss2/7