Anti-first-strike Countermeasures
According to the theory of nuclear deterrence and mutually assured destruction, full countervalue retaliation would be the likely fate for anyone who unleashed a first strike. So as to maintain credible deterrence, the nuclear-weapons states have taken measures to give their enemies reason to believe that a first strike would lead to unacceptable results.
The main strategy here relies on creating doubt among enemy strategists regarding nuclear capacity, weapons characteristics, facility and infrastructure vulnerability, early warning systems, intelligence penetration, strategic plans, and political will. In terms of military capabilities, the aim is to create the impression of the maximum possible force and survivability, leading the enemy to make increased estimates of the probability of a disabling counterstrike; while in terms of strategy and politics, the aim is to cause the enemy to believe that such a second strike would be forthcoming in the event of a nuclear attack.
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