Today, missile fields are spread out across three bases: the smallest, at Minot Air Force Base in North Dakota, covers some 22,000 sq km (8,500 sq mi). “That’s roughly the size of the state of New Jersey,” Klotz says.
Arms control experts agree that a mobile ICBM force is probably not around the corner. The recent Air Force announcement “is a preliminary first step to explore theoretical options for replacement of the Minuteman III ICBM force,” says Daryl Kimball, executive director of the Washington DC-based Arms Control Association.
Kimball points out that the US has cut its nuclear arsenal in recent years - there are currently just 420 Minuteman IIIs, and to invest now in an entirely new system makes little sense. “The reality is that the current plans for modernising the strategic triad, which were developed years ago, is too costly given the current budget environment,” he says.
The idea of putting a nuclear weapon on a moving vehicle is also too risky, according to Hans Kristensen, director of the Nuclear Information Project at the Federation of American Scientists. “This notion of rolling around on country roads and rural areas, with an increased risk of accidents, seems to be a step back in this day and age,” he says.
But this is not the first time the Air Force has looked at mobile ICBMs, Kristensen notes. In the 1980s, the government debated putting the Peacekeeper missile on trains, or even “race tracks.”
“At the end of the day, all these options were way too expensive and they ended up in silos,” he says. “You can come up with fancy ideas, but the reality check at the end of the day is: what is needed, what is necessary, and how much can we afford?”
The mostly like outcome is that the United States will simply keep the Minuteman III, and refurbish it as it has done before. It just finished a multi-billion dollar refit, which involved updating everything from fuel to guidance parts, and the end result is a nearly “new” missile.
Repeating that refurbishment to keep the Minuteman III going until 2075 is the most likely path for the Air Force, according to Kristensen. “Mobile and tunnel systems, that’s a pie in the sky,” he says.
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