This study examines the transformation of nuclear deterrence in the age AI by analyzing its core foundations, particularly the doctrine of the second strike, the balance of terror, and the credibility of threat, while explaining how deterrence has helped reduce the risk of large-scale nuclear war since the end of World War II. It argues that integrating AI into sensing, analysis, and decision making does not dismantle deterrence but reshapes the conditions of its stability by reducing uncertainty and compressing decision time during crises, thereby increasing the risks of miscalculation and enhancing the appeal of counterforce strategies​.