Convinced that we require a broader range of nuclear options to ensure a credible deterrence threat, the National Nuclear Security Administration (NNSA) has begun studying the creation of a Robust Nuclear Earth Penetrator (RNEP), a nuclear bomb that would slam into the ground and detonate a few meters below the earth’s surface. Proponents claim that the weapon is needed to attack deeply buried and hardened targets, but RNEP is worthless as a surgically precise tool, and of highly dubious value as a nuclear deterrent.

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