The LGM-35 Sentinel, also known as the Ground Based Strategic Deterrent (GBSD), is a future American land-based intercontinental ballistic missile system (ICBM) currently in the early stages of development.

[3][5] In 2020, the United States Department of the Air Force awarded defense contractor Northrop Grumman a $13.3 billion sole-source contract for development of the LGM-35 after Boeing withdrew its proposal.

Northrop Grumman's subcontractors on the LGM-35 include Lockheed Martin, General Dynamics, Bechtel, Honeywell, Aerojet Rocketdyne, Parsons, Textron, and others.

[6][7][8] On January 19, 2024, the United States Air Force (USAF) announced that the program’s costs had risen to over $125 billion—37% above the initial $95.3 billion budget—and its deployment would be delayed by two years.

[11] According to the United States Air Force website,[12] the L in LGM is the Department of Defense designation for silo-launched; G means surface attack; and "M" stands for guided missile.

[18] The Air Force subsequently halted funding for the Boeing project, leaving Northrop Grumman as the sole bidder for the contract by October 2019.

[20] On 8 September 2020, the Department of the Air Force awarded Northrop Grumman a $13.3 billion contract to develop the GBSD intercontinental ballistic missile.

[23] In April 2023, the USAF formally began seeking vendor information preliminary to issuing a request for proposal (RFP) for the Next-generation reentry vehicle (NGRV).

[32] In its annual 2021 Threat Assessment, the US Intelligence community said China was planning to double its arsenal of nuclear weapons over the next ten years in "the most rapid expansion in its history."

"[34] Jennifer Granholm, Secretary of Energy in the Biden administration, told the press on April 9, 2021, "We have to keep and maintain the stockpile to make sure that it is safe and effective, and we will continue to do that to ensure that we can deter nuclear aggression from other countries.

[40] Wright concludes that the vulnerability of ICBMs has prompted the Air Force to keep them on high alert, which is dangerous and could trigger a nuclear war.

[40] According to William Hartung, author of Prophets of War: Lockheed Martin and the Making of the Military-Industrial Complex, a president would have only minutes to decide whether to launch ICBMs in a crisis so that the missiles would not be destroyed in a first strike.

[41] In 2020, the Program for Public Consultation at the University of Maryland, issued a report entitled Common Ground of the American People, which was a compilation of studies conducted over the previous five years, collecting data from nearly 86,000 individuals who were polled on the GBSD.

[42] Another 2020 poll conducted by the Federation of American Scientists and ReThink Media found a majority of both Republicans and Democrats favored alternative solutions to the GBSD, including extending the life of the Minuteman III ICBM.

During a spring 2021 event hosted by the Washington, D.C.–based Advanced Nuclear Weapons Alliance, Tester said he was committed to keeping the GBSD "on track" though added there will be debate about the proposed new missiles during the 2022 defense appropriations process.

[49] According to the Arms Control Association, Caucus Senators received the following contributions from military contractors from 2012-2020: Romney ($645,000); Tester ($102,360); Barasso ($89,000); Daines ($85,948); Enzi ($68,500); Cramer ($49,593).