What is the central idea behind the concept of 'Minimum Deterrence'?

The central idea behind the concept of 'Minimum Deterrence' is that a state needs to possess only a sufficient amount of nuclear weapons to inflict unacceptable damage on a potential adversary, even after absorbing a first strike. This level of damage must be high enough to deter the adversary from initiating an attack in the first place. Minimum deterrence does not require matching an adversary's nuclear arsenal size or pursuing escalation dominance. Instead, it focuses on ensuring a credible second-strike capability. This means maintaining a nuclear force that can survive a surprise attack and still retaliate with enough force to inflict unacceptable damage on the attacker's cities, industrial centers, and population. The specific size and composition of the nuclear force required for minimum deterrence will vary depending on the adversary's vulnerabilities and the definition of 'unacceptable damage'. Some proponents of minimum deterrence argue that it is a more stable and less expensive deterrence strategy than maintaining a large and diverse nuclear arsenal. It reduces the risk of accidental war by lowering the alert status of nuclear forces and reducing the incentives for a preemptive strike. However, critics argue that minimum deterrence may not be credible against all adversaries or in all situations, and that it may not be sufficient to deter limited nuclear attacks or non-nuclear aggression. Despite these criticisms, minimum deterrence remains a significant concept in nuclear strategy and arms control.