International Security

Recent quantitative scholarship uses warhead counts to examine whether nuclear superiority offers political or military benefits beyond having a secure second-strike capability. These analyses overlook other elements of a state’s nuclear capability such as state perceptions and beliefs.

The costly Ground-based Midcourse Defense system remains unproven and unreliable in deterring North Korea’s threat to use intercontinental ballistic missiles. An airborne boost-phase intercept system may offer an alternative defense against North Korea without threatening Russian or Chinese deterrents.

Could a conventional war between China and the United States escalate to the nuclear level? An assessment of three mechanisms of China-U.S. inadvertent escalation—use-it-or-lose-it, unauthorized/accidental, and damage limitation—concludes that the risk of China-U.S. inadvertent nuclear escalation is extremely low.

Christopher Ford, John Harvey, Franklin Miller, Keith Payne, and Bradley Roberts respond to Scott Sagan and Allen Weiner’s spring 2021 article, “The Rule of Law and the Role of Strategy in U.S. Nuclear Doctrine.”

When properly applied, the key principles of the law of armed conflict have a profound impact on U.S. nuclear doctrine. Specifically, it would be unlawful for the United States to intentionally target civilians, even in reprisal for a strike against U.S. or allied civilians.

Carpenter and Montgomery replicate a key question from Sagan and Valentino’s landmark survey of U.S. attitudes toward the laws of war and introduce variations into Sagan and Valentino’s experiment. The findings reveal Americans’ strong belief that targeting civilians is wrong, and that a majority would likely oppose such action in real life.

Scott Sagan and Benjamin Valentino, and Charli Carpenter and Alexander Montgomery continue the debate on the power of noncombatant immunity norms, discuss how scholars should approach the study of these norms, and emphasize their shared objective to determine how security norms can be bolstered rather than undermined.

China and the United States hold opposing beliefs about whether nuclear war can be avoided in a potential crisis or armed conflict. Taken together, these opposing beliefs increase the risk of nuclear escalation and can lead to greater crisis instability.