Cost of modernizing US Air Force’s nuclear missile arsenal increases by over 80%

The US Air Force’s project to modernize its nuclear missile arsenal is projected to cost approximately $141 billion, which is roughly 81% more than previously anticipated, and will be delayed by several years, officials said Monday.

A review of the Sentinel program was conducted after the Air Force said in January its costs were exceeding baseline projections. The review found that the cost of the program is estimated to be $140.9 billion — an 81% increase from the cost estimate made in September 2020.

The Sentinel program is a massive effort to replace the Minuteman III intercontinental ballistic missile system, which was introduced in the 1970s, with Sentinel intercontinental ballistic missiles. According to Air Force Global Strike Command, the Sentinel will extend the US’ land-based nuclear capabilities “through 2075.”

“There are reasons for this cost growth, but there are also no excuses,” Dr. Bill LaPlante, the under secretary of defense for acquisition and sustainment, said on Monday. “We fully appreciate the magnitude of the cost, but we also understand the risks of not modernizing our nuclear forces, and of not addressing the very real threats we confront.”

As a result of the cost increase, LaPlante said he has directed the Air Force to restructure the program and put an “appropriate management structure” in place to control costs — which will delay it by “several years.” He also rescinded approval for it to enter the engineering and manufacturing development phase.

Typically, if the costs of a program increase by 25% or more, it has to be terminated unless the under secretary of defense for acquisition and sustainment “certifies to Congress that the program meets established criteria to continue,” a news release on Monday said.

LaPlante told reporters on Monday he was doing exactly that. He said the modernization program is “essential to national security,” and is higher priority than programs whose funding will need to be cut to accommodate the rising costs with “no alternatives” that would match the Sentinel program’s capabilities for a lower price.

LaPlante attributed the inaccuracy of the original cost estimate to insufficient knowledge on a piece of the program. Vice Chief of Staff of the Air Force Gen. Jim Slife added Monday that decisions on of what funding trade-offs the Air Force will need to make in order to fund Sentinel won’t need to be decided for another few years.

After what LaPlante called a “comprehensive, unbiased review” of the program, he determined it was clear that a modified version of the program “remains essential to US national security.”

“It’s important to note that Sentinel is truly a historic program to modernize the land leg of the nuclear triad, and its scale, scope, and complexity are something we haven’t attempted as a nation for over 60 years,” LaPlante said. “Across the department, we are committed to ensuring we are on the right path to defend our nation while protecting the sacred responsibility the American taxpayer has entrusted us with.”

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