They've laid dormant at hundreds of hidden sites for nearly 75 years, silently protecting Americans.
Now the nation's nuclear missiles are about to get a $141 billion upgrade that will enable them to launch counter attacks on adversaries like Russia and China.
The plan, called Sentinel, will modernize the US military's 450 silos and construct 3,100 miles of utility corridors and build 62,300-foot communication towers by 2036.
The costs could balloon to more than $300 billion after Sentinel is completed, but officials have stated that the plan 'is essential to national security' and 'are no alternatives' that would lower pricing.
The DOD has scheduled a Congressional hearing for July 24 that will go over plans to restructure 450 intercontinental ballistic missiles (ICBMs) launch facilities and the weapons they house.
These silos are scattered across 40,000 square miles of the northern Midwest, specifically throughout North Dakota, Montana, Colorado, Wyoming, and Nebraska.
The silos were constructed in the 1950s to store nuclear-armed missiles that could be quickly launched during the Cold War.
But the arsenals and launch facilities have not been updated since.
Dr William LaPlante, who served as the DoD lead for the review, said in a July 8 statement: 'Sentinel is a truly historic program to modernize the land leg of the Triad, and its scale, scope, and complexity are something we haven't attempted as a nation in 60 years.
'Having completed a comprehensive and objective assessment of the program, it is clear that the Sentinel program remains essential to US national security and is the best option to meet the needs of our warfighter.'
The current state of America's nuclear arsenal remains safe, secure, and effective,' the Pentagon review shared.
However, most of the systems are operating beyond their original design life, and there is little or no margin between the end of their effective life and the fielding of their replacements.
The billion-dollar upgrades, according to the review, are necessary to ensure there are now gaps in national security as America's adversaries have poured even more money into ensuring their arsenals are up-to-date.
General David W. Allvin, Chief of Staff of the Air Force, said: 'We face an evolving and complex security environment marked by two major nuclear powers that are strategic competitors and potential adversaries.
While I have confidence in our legacy systems today, it is imperative that we modernize of our nuclear Triad. A restructured Sentinel program is essential to ensure we remain best postured to address future threats.
Sentinel marks the DOD's largest nuclear weapons project since the end of the Cold War when the US built a triad of ICBMs, SLBMs (Submarine-launched ballistic missiles) and heavy bombers - creating an arsenal of 10,000 nuclear warheads.
The Air Force is expected to start replacing the existing Minuteman III ICBMs in 2030, and while the DOD believes it will cost $141 billion - an 81 percent increase from their 2020 projections - a 2024 taxpayer analysis claimed the real total cost will likely be closer to $315 billion.
The original Minuteman silos were put in place so the US could launch a nuclear attack on Russia or China if the need arose, which would obliterate the entire population but would also serve as a 'nuclear sponge.'
The 'nuclear sponge' theory is that ICBMs would destroy hundreds of warheads from an adversary like Russia before the country could launch them at the US.
'When I was on the Armed Services Committee staff in the '80s and '90s, I heard about the sponge,' Joseph Cirincione, a former congressional staffer who worked on military reform for almost a decade, told WIRED.
'It's one of the two chief justifications for the ICBM.'
Sentinel's goal is to complicate an adversary's plan to launch an attack on the US to the point that it would discourage the foreign government from attacking.
The response comes as China's arsenal is quickly advancing as the country is on track to possess at least 1,000 nuclear weapons by 2030 while Russia has the largest nuclear stockpile of 5,580.
While the plan is crucial to the survival of Americans, experts have warned that this so-called 'doomsday machine' could kill upwards of 300 million people living around the launch sites.
The DOD said in a report earlier this month that 'the Sentinel program is essential to national security' and said there are risks associated with not updating the ballistic missiles.
'If we used the ICBMs it would be the end of human civilization, even without an adversary hitting the US with a single warhead,' said Cirincione.
However, speaking about how many deaths the ICBMs could cause, Princeton University's lead researcher Sébastien Philippe told WIRED: 'It's not just absorbing a nuclear attack.
'It's like when you pour water on the sponge, and then you press onto it, it's going to spill everywhere. So spill-out from that sponge is massive radioactive fallout across the country,' he continued.
'We're not talking about having cancer in 15, 20, 30 years.
'We're talking about your cells and organs and your body shutting down in days, weeks, or months after the explosion.'
The Air Force revealed in March that nearly 200 missile officers who served at Malmstrom Air Force Base in Montana which is located near a silo site have been diagnosed with cancer, and at least 23 had non-Hodgkin lymphoma - a blood cancer.
Researchers at Princeton University's program on science and global security studied the ramifications of the 'human and environmental risks associated with the Sentinel missile program'.
They said there are 'catastrophic risks' associated with deploying ICBMs.
The missiles would also generate hazardous waste that could contaminate streams with asbestos, lead-based paint and polychlorinated biphenyls.
These chemicals have been linked to liver and kidney damage, cancer and immune and reproductive issues, according to a Princeton University study.
Researchers also reported that the US Air Force has found unsafe levels of a possible carcinogen at underground launch control centers in Montana.
Many have opposed the government's plans, including Former Secretary of Defense William Perry warned that the ICBMs should be eliminated in a 2016 New York Times op-ed.
He called the missiles 'some of the most dangerous weapons in the world,' adding that 'they could even trigger an accidental nuclear war' and described a false alarm he experienced when a computer glitch claimed 200 Soviet nuclear missiles were heading toward the US.
The US Air Force released an Environmental Impact Statement in March of last year that claimed land-based missiles and silos 'do not involve nuclear material,' even though each missile will be built carrying a nuclear warhead that has the explosive power equivalent to hundreds of thousand tons of TNT.
'Russia and the United States have already been through one nuclear arms race. We spent trillions of dollars and took incredible risks in a misguided quest for security,' Perry wrote in the op-ed.
He added: 'There is only one way to win an arms race: refuse to run.'
A Pentagon spokesperson declined DailyMail.com's request for comment on the claims and said 'further information will be made available as the restructuring for the program moves forward.'
