The US Department of Defense will continue developing its new Sentinel intercontinental ballistic missile (ICBM) despite an 81% increase in costs as Washington seeks to update its ‘nuclear triad’.
The Sentinel ICBM program, which is intended to replace aging Minuteman III nuclear missiles, is now expected to cost $140.9 billion – almost double the original estimate of $77.7 billion, the Pentagon said in a statement on Monday.
The ballooning cost of the nuclear warhead program has triggered what is known as a Nunn-McCurdy breach, which occurs if the cost of developing a new program increases by 25%, and requires a Department of Defense review to justify its continuation. Following this review, the Pentagon has found that there are no viable alternatives to the Sentinel.
William LaPlante, the under secretary of defense for acquisition, said his office was “fully aware of the costs.”
“But we are also aware of the risks of not modernizing our nuclear forces and not addressing the very real threats we confront,” he added in the statement.
Much of the cost increase has been attributed not only to building the new missile but also to the large-scale modernization of ground-based facilities, including launch control centers, nuclear missile bases, and testing facilities.
The approval of the Sentinel ICBM attracted considerable criticism, prompting more than 700 US scientists representing institutions across the country to send a letter to US President Joe Biden and Congress on Monday. The scientists urged the Pentagon to drop the “expensive, dangerous, and unnecessary” nuclear warhead program.
They argued that “there is no sound technical or strategic rationale for spending tens of billions of dollars building new nuclear weapons.”
“These weapons – stored in silos across the Plains states – place a target on communities and increase the risk of nuclear war while offering no meaningful security benefits,” said Tara Drozdenko, director of the Global Security Program at the Union of Concerned Scientists.
The size of the US nuclear arsenal is currently limited by New START, a treaty negotiated with Russia in 2010. It is set to expire in 2026, with no indications that it might be renewed.
Last year, Russia formally suspended its participation in New START, citing US sanctions over the Ukraine conflict and encouragement of Kiev’s attacks on Russian strategic air bases. However, Moscow has continued to observe the treaty’s provisions, capping its number of nuclear weapons and delivery systems.