Senior Pentagon officials have announced that a new, nuclear-armed, submarine-launched, low-yield ballistic missile warhead is now operational.
The announcement brings a new measure of potential precision nuclear attack strikes to the Department of Defense's current deterrence posture. The weapon called the W76-2 low-yield submarine-launched ballistic missile, “demonstrates to potential adversaries that there is no advantage to limited nuclear employment, because the United States can credibly and decisively respond to any threat scenario,” John Rood, Under Secretary of Defense for Policy, announced in a Feb. 4 Pentagon statement.
The now operational weapon, Pentagon officials tell Warrior, is now “fielded.” The new weapon does seem to have emerged quickly, as initial draft plans were underway just within the last year or two. Significantly, Rood’s statement specifically cites that Russia may “believe that employment of low-yield nuclear weapons will give them an advantage over the United States and its allies and partners.” He adds that U.S. counterattack options ensure a “prompt” response.
One tactical advantage to a weapon of this kind, naturally intended to prevent nuclear war, is that it ensures a catastrophic, yet targeted nuclear response option in the event the U.S. is attacked with nuclear weapons.
Pentagon officials tell Warrior the low-yield missile warhead and the missile’s re-entry body, involves a modification of the existing Trident II D5 submarine-launched, nuclear-armed ballistic missile. Re-entry bodies are the parts of a nuclear-armed missile that re-enter the earth's atmosphere carrying the warhead.
“The low-yield warhead is engineered for a submarine-launched ballistic missile,” the official said.
The modification effort is intended to align with the DoD’s Nuclear Posture Review (NPR) released two years ago by the Trump administration and Pentagon, which calls for the introduction of several new lower-yield nuclear weapons.
The 2018 Nuclear Posture Review identifies a requirement to “modify a small number of submarine-launched ballistic missile warheads.”
The new SLBM brings a third warhead option to a nuclear attack. As it currently stands, the Trident can carry the W76-1 or W88, Pentagon officials have told Warrior.
Low-yield is as it sounds -- smaller, more surgical and less destructive than most nuclear weapons. While some experts say a low-yield weapon could be in the range of 20 kilotons, senior Pentagon officials tell Warrior “there is no formal definition of what is low yield and what is not. It is a term of art used in arms control but we have not set a limit.”
Many existing nuclear weapons are often in the range of 90 to 100 kilotons, or more.
This low-yield nuclear missile option does appear to add something not currently present in the U.S. arsenal. While the emerging B-21 will be configured to fire lower-yield, more precise B61 Mod 12 weapons, a sub-launched nuclear weapon brings newer avenues of attack and long-range strike without having to operate air assets over or near heavily defended areas. The F-35 is also being engineered to carry nuclear weapons.
Yet another proposed nuclear weapons application, according to those identified by the NPR, is a shorter-range sea-launched cruise missile. Nuclear cruise missile options, potentially fired from a submarine or ship, can bring even more precision, Han Kristensen, Nuclear Information Project at the Federation of American Scientists, told Warrior in an interview last year.
A sea-launched cruise missile could include a handful of possibilities. The Pentagon previously had a nuclear-armed Tomahawk missile, which was retired in 2011.