Second strike
In nuclear strategy, a retaliatory strike or second-strike capability is a country's assured ability to respond to a nuclear attack with powerful nuclear retaliation against the attacker.[1] To have such an ability (and to convince an opponent of its viability) is considered vital in nuclear deterrence, as otherwise the other side might attempt to try to win a nuclear war in one massive first strike against its opponent's own nuclear forces.
Theory[edit]
The possession of second-strike capabilities counters a first-strike nuclear threat and can support a no first use nuclear strategy. Reciprocal second-strike capabilities usually cause a mutual assured destruction defence strategy, though one side may have a lower level minimal deterrence response.
Second-strike capabilities can be further strengthened by implementing fail-deadly mechanisms. These mechanisms create a threshold and guaranteed consequences if that threshold is breached. For instance, a threshold may be for an allied nation not to be attacked. If a rival nation then breaches this threshold by attacking the allied nation, then the predetermined consequences for this action go into effect. These predetermined consequences could include a wide range of responses, including a retaliatory nuclear second strike.
History[edit]
As early as 1940, science fiction writer Robert A. Heinlein wrote the science fiction short story Solution Unsatisfactory in which he described a nuclear arms race between the United States and the Soviet Union. In one episode, the US cabinet discusses the scenario of a Soviet surprise attack in which American cities would be destroyed, but the US armed forces would survive and launch a counter-attack.