What makes deterrence by punishment an effective means of control?

Deterrence by punishment is an effective means of control because it relies on the threat of inflicting unacceptable costs or pain on an adversary if they undertake a specific action. The effectiveness stems from the rational calculation that the potential consequences of the action outweigh any perceived benefits. This calculation depends on several key factors: the severity of the threatened punishment, the credibility of the threat, and the adversary's perception of their vulnerability. The more severe the threatened punishment, the greater the deterrent effect. However, the punishment must also be proportionate to the action being deterred; otherwise, the threat may not be credible. Credibility is essential for deterrence by punishment to be effective. The adversary must believe that the state is both willing and able to carry out the threatened punishment. This requires demonstrating a commitment to defending vital interests and a history of following through on threats. The adversary's perception of their vulnerability also plays a role. If the adversary believes that they are invulnerable to the threatened punishment, deterrence by punishment will be ineffective. This is why states often invest in defenses to protect themselves from retaliatory attacks. For example, in nuclear deterrence, the threat of massive retaliation against an adversary's cities and population centers deters them from launching a nuclear attack in the first place. The effectiveness of this deterrence relies on the credibility of the threat and the adversary's perception of their vulnerability to nuclear attack. Therefore, the power of deterrence by punishment comes from the targeted party rationally concluding that the consequences are too great to bear, thus making the undesired action self-defeating.