Effectiveness
Nuclear blackmail is considered most effective when the person making the threat is unhinged and ostensibly willing to commit suicide. (See game theory). The prevention of these threats by irrational actors is the stated purpose behind the National Missile Defense program undertaken by President George W. Bush of the United States.
It is generally regarded as ineffective against a rational opponent who has or is an ally of someone who has assured destruction capability. If both states have nuclear weapons, the form of nuclear blackmail becomes a threat of escalation. In this situation if the opponent refuses to respond, then one's choices are either surrender or suicide. During the Cold War, the explicit threat of nuclear warfare to force an opponent to perform an action was rare in that most nations were allies of either the Soviet Union or the United States.
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