Why America Never Went All In On Mobile Nuclear Missiles

Mark Episkopos

Security, Americas

The military realized these weapons actually would cause more problems than they solved.

Mobile intercontinental ballistic missile (ICBM) systems have long been viewed as a major boon to survivability and strategic flexibility. Both the Soviet Union and its Russian successor have invested heavily into such systems, and they comprise a vast chunk of the Kremlin’s contemporary strategic arsenal. But the U.S. military never followed suit. Here are the reasons why.

Amid a growing threat from increasingly potent Soviet strategic submarines equipped with submarine-launched ballistic missiles (SLBMs), the U.S. security establishment began to explore the costs and benefits of mobile ICBM systems. The strategic premise is fairly straightforward: missile silos are deeply vulnerable to a first strike. Given their static nature, they are impossible to conceal and difficult to defend against a saturation attack. Road mobile ICBMs, on the other hand, are extremely difficult to identify, track, and neutralize. They can strike from anywhere, potentially with no forewarning. Even if the enemy did manage to identify them quickly enough, reliably eliminating well-placed mobile ICBM’s will be a major drain on their time and valuable strike resources—two factors that are bound to be in short supply in the event of an all-out nuclear conflict.

If all that sounds too good to be true, that’s because it partly is; the process of maintaining, moving, and effectively deploying mobile ICBMs poses a slew of logistical problems that are not readily apparent. The United States did, in fact, dabble with mobile systems. Conceived in the 1980s, the MGM-134A Midgetman was a prototype three-stage solid-fueled missile transported by a hard mobile launcher (HML). Boasting a range of roughly 11,0000 kilometers and compatible with several types of warheads, the Midgetman was designed around the concept of rapid deployment.

But there was no shortage of problems. As also discovered by the Soviets and Russians, mobile ICBMs are notoriously expensive to produce and maintain. The Midgetman’s introduction in the mid 1980s spawned a fierce debate over its cost, with detractors charging that broadly similar strategic effects—namely, survivability and flexibility—could be achieved for much cheaper by investing in, among other things, more strategic submarines. But let’s assume that cost is no object; still, there are significant conceptual issues. Mobile ICBM systems are heavy and will need to be equipped with sufficient radiation protection—even then, they pose clear environmental hazards. If they can only be driven on paved roads, that makes them somewhat easier to track—this is more of a problem for countries with poor road infrastructure like North Korea, but it can still pose operational issues in certain regions of the United States.

It’s also worth noting that these types of mobile ICBMs must be stationed in static garrisons or missile bases according to the New START treaty, which President-elect Joe Biden is set to extend during his early days in office. In such a state, mobile ICBMs are no more survivable than their silo-launched counterparts. A mobile ICBM force has to be constantly and efficiently dispersed in order to be survivable, introducing a new round of expenses and logistical headaches.

The Midgetman project was shelved shortly following the Soviet collapse. As convincingly argued in a 2015 Air University paper, the need for a mobile ICBM deterrent could be revisited if the survivability of U.S. strategic submarines is credibly threatened, or if American silo-launched ICBM’s become vulnerable to conventional strikes. As it stands, mobile ICBMs saddle the U.S. military with more problems than they solve.

Mark Episkopos is the new national security reporter for the National Interest.

Image: Reuters.