Nuclear Modernization, ICBMs, and Launch On Warning

The US is replacing all three legs of the triad, ballistic missile submarines (SSBNs), bombers, and intercontinental ballistic missiles (ICBMs), at a cost of over $1.2 trillion. The SSBN force is the core of the deterrent because it can survive a Russian attack and deliver a devastating retaliatory strike. The strategic bomber can support conventional missions and the cost of adding a nuclear capability is modest. But silo-based ICBMs are not survivable; they can be destroyed in a first-strike. For this reason, ICBMs are kept ready to be launched on warning of a Russian attack. This forces decisions to be made in minutes and creates the possibility of launch on false warning.

Two arguments are made in favor of retaining a ICBMs. First, ICBMs are a hedge against failures in other legs of the triad. But ICBMs cannot serve as a hedge unless the US commits to launch under attack. Second, without the 400-plus aimpoints provided by ICBMs, Russia might be tempted to strike the small number of remaining targets. Why Russia would take this risk knowing that SSBNs armed with over 700 warheads would remain capable of delivering a devastating retaliatory strike is unclear. The key is the survivability of command, control, and communication capabilities.