Nuclear entanglement: The growing threat to command and control James M. Acton jacton@ceip.org

What is entanglement? Nonnuclear threats (real or perceived) to nuclear forces and their C3I capabilities Dual-use C3I capabilities Dual-use weapons and nuclear weapons that are superficially similar to nonnuclear weapons Co-located nuclear and nonnuclear weapons and C3I capabilities Nuclear deterrence against nonnuclear threats

Drivers of entanglement Increasingly capable nonnuclear weapons Anti-space, high-precision conventional, and cyber weapons Reduction in the redundancy of the U.S. nuclear C3I system Some ageing capabilities scrapped without replacement Greater standardization of components for different nuclear delivery systems Increasing reliance on dual-use C3I assets SBIRS PAVE PAWS/UEWRs Growing doctrinal emphasis on attacking C3I capabilities China, Russia, and the United States

Incidental attacks Entanglement is increasing the risk of “incidental attacks” Attacks against SBIRS to enable nonnuclear regional ballistic missiles to penetrate missile defenses Risk that nuclear C3I architecture is degraded over the course of a conventional conflict Escalation risks Crisis instability Misinterpreted warning Damage-limitation window

SBIRS vulnerability SBIRS involved in both nuclear and nonnuclear operations Early warning of a nuclear attack SBIRS HEO detectors reportedly hosted by electronic-intelligence collection satellites Nonnuclear ballistic missile defense Even limited strikes could undermine nuclear early-warning capability Polar early-warning represents a single-point vulnerability Potential SSBN patrol in N Atlantic areas represent a dual-point vulnerability Dual phenomenology means there is no redundancy at a systems level

Basic approaches to risk reduction Reducing the likelihood of attack Need to shape adversary perceptions Necessarily acknowledged Reducing the consequences of attack No need to shape adversary perceptions Possibly secret These objectives can be in tension Entanglement as a deliberate strategy Counter example: Building more systems

Reducing the likelihood of attack Disaggregation of early warning impossible Dual-capable missiles Dispersed supplements to SBIRS with capability limitations Hosted system, cf AFSATCOM Challenge of convincing adversaries about limitations Risk of weakening deterrence of attacks against SBIRS Small, low resolution, dispersed detectors More useful for early warning than BMD or other missions Exo-atmospheric missile detectors Tuned to IR frequency that is absorbed by the atmosphere Only able to detect long-range missiles

Reducing the consequences of attack Medium resolution, dispersed detectors Hosted system Open alternative to SBIRS (trade redundancy for capability) Secret supplement to SBIRS (challenge to keep secret) Weather satellite back-up Secret supplement to SBIRS Probably need to build the right frequency band into future satellites Allied weather satellites best placed