By the middle of this century, a large chunk of the United States’ nuclear arsenal could be located on a doomsday subway system, where unmanned cars move back and forth on a single track, prepared to launch at a moment’s notice.
Or a least that’s one of several ideas that the Air Force is potentially mulling over as it prepares to replace its decades’ old intercontinental ballistic missiles (ICBMs). To jumpstart those preparations, the Air Force earlier this month released an open call for proposals that would help the Air Force decide what the future land-based nuclear force would look like for the 50-year period starting in 2025.
At stake is a part of the nation’s rapidly aging nuclear arsenal, which consists of the "triad" of land-based ICBMs, submarine-launched missiles, and bombers armed with nuclear weapons.
Supporters of this deterrent argue that, despite the end of the Cold War, it is still needed to deter a potential enemy from threatening the United States with nuclear weapons, or even other weapons of mass destruction. “The official reason is still one of flexibility, and survivability in the event of a nuclear attack,” says Ivan Oelrich, a long-time defense analyst and expert on nuclear issues. “The real unspoken argument is bureaucratic inertia.”
In recent years, some US Pentagon officials have questioned whether keeping all three elements of this costly triad is really needed, though no changes have yet been made. In the meantime, parts of the system are rapidly approaching their use by date. The current ICBM, the Minuteman III, is expected to reach the end of its life by 2030.
Of the five different ideas the Air Force is currently exploring, the underground tunnel concept would be one of the more dramatic changes from the current system, which has missiles located in fixed, underground silos spread out across three bases. The tunnels would in theory allow the missile to survive direct nuclear attacks, since an enemy wouldn’t know precisely where the missile is located at any given time.
“The tunnel concept mode operates similar to a subway system but with only a single transporter/launcher and missile dedicated to a given tunnel,” the Air Force says. “The vehicle moves at random down the length of the tunnel.”
That, however, is not the only possible new system. Another concept involves putting the missiles above ground, perhaps on specialised vehicles called “transporter erector launchers.” Those vehicles may have to venture on to public roads or lands, according to the Air Force, or even travel off road.
While the idea of off-road vehicles and underground trains transporting nukes may sound wild, the Air Force says it’s also considering more basic options, such as simply keeping the current Minuteman III through until 2075, or undertaking modifications to the system. Yet another option would be building a new missile that would replace the Minuteman, but still use underground silos.
None of these proposals are right around the corner, cautions retired Lt. Gen. Frank Klotz, who last served as the commander of Air Force Global Strike Command, which is responsible for the US ICBMs, as well as nuclear-armed bombers. “The purpose of sending out the request for concepts is to flesh out the ideas in greater detail so that at some point, they can be subjected to intense analysis as to the cost, feasibility, and operational effectiveness,” says Klotz, who is now a senior fellow at the Council for Foreign Relations.
While any such proposal for underground tunnels or mobile ICBMs is likely far off in the future, he says that such options are not necessarily more expensive in the long run, since it would allow the Air Force to consolidate its operations. When the Minuteman missile was first deployed some 50 years ago, the concept was to disperse them to reduce their vulnerability to a Soviet attack. But maintaining and protecting missiles over such a large area, such as paying for vehicle fuel, can be burdensome.