In the cold, lonely silence at the bottom of a U.S. missile silo, officers sit near the leashed rage of a nuclear missile, waiting for the order to send it roaring toward its target.
They wait, and wait. But if the order comes to launch the missile, it has to be carried out instantly.
“When you’re down there, as I was, 100 feet underground, you get a burst of alphanumeric values that come in an encoded message, and once you get that transmission you have seconds to execute it,” says John Noonan, a former nuclear launch officer who was national security policy advisor to Republican hopeful Jeb Bush.
“So the people on the trigger end of this process really don’t have the time to sit there and navel-gaze about whether or not the order is authentic, or for a valid reason.”
Being the officer at the bottom of the silo means having unconditional trust in the president, who would have issued a launch order only a few minutes before.
On Wednesday, Noonan wrote an anguished series of tweets opposing Republican presidential candidate Donald Trump’s candidacy from the point of view of someone who had once been ready to help launch a nuclear weapon:
The most dramatic, and least restricted, of a U.S. president’s many powers is the authority to order a nuclear attack. Trump’s past statements about how he would use it have alarmed many.
He has said repeatedly that a president’s use of nuclear weapons should be “unpredictable”. If nuclear weapons can’t be used, “why are we making them?” he asked on another occasion.
In a debate in December, Trump appeared to have never heard of the “nuclear triad,” a basic concept if you’re aspiring to a job that involves having the power to use nuclear weapons. (The term refers to the three different parts of the U.S. nuclear arsenal: bomber-launched missiles, silo-launched intercontinental ballistic missiles, and submarine-launched missiles.)
“What good does it do to have a good nuclear triad if you’re afraid to use it?” Trump spokesperson Katrina Pierson asked in December.
Under the harsh Cold War logic that still governs the system, a nuclear enemy has to be assured that a retaliatory strike can be ordered instantly. Taking time for debate, or even reflection, could lead to obliteration.
It’s a dark bargain, in which we’ve successfully avoided a war between major powers in exchange for entrusting political leaders with apocalyptic powers of destruction.
So if a U.S. president orders a misguided or inappropriate use of nuclear weapons, what could stop it from being carried out?
Very little, says Princeton University professor Bruce Blair, himself a former nuclear launch officer.
Officers who refused to co-operate, and were willing to accept the consequences, might try to obstruct a nuclear attack:
“Our last best hope for sanity would be that some in the chain of command would decide to ignore, refuse, or otherwise neutralize this order from the President. It goes beyond legal and illegal, although there is also international humanitarian law.”
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However, the nuclear launch system is designed to survive being attacked itself, and also to carry out a launch order with extreme speed. Both of those things act against a nuclear mutiny actually working, Blair says.
The redundancy that’s built into the nuclear command system that allows it to absorb an attack would also let it work around dissenting officers who refused to obey launch orders.
“(The launch codes) are concentrated at a number, quite a number, of primary and alternate command posts. There is the possibility that if a president couldn’t get satisfaction from the Pentagon, he could maybe get it from Strategic Command, which is an alternate command post in Omaha, Nebraska.”
“If you had opposition in Washington, it provides a bypass to provide launch orders to the forces.”
The speed of decision-making in the nuclear launch process — designed to get missiles in the air before their launch sites can be destroyed — would also work against organized dissent.
“The structure was organized at the beginning of the nuclear weapons age, and reflects the facts that missiles can fly across the planet in 30 minutes, or from submarines in the Atlantic Ocean to Washington in 15 minutes,” Blair says.
“It was all designed for very rapid reaction, and there are very few checks and balances that can be imposed on that kind of a timeline.”
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“If the president woke up on the wrong side of the bed, with some paranoid idea that an attack against the United States is imminent, that we needed nuclear weapons to solve a problem, or just decided that nuclear weapons were the right tool for the moment to deal with some threat from North Korea, or some terrorist threat, then he has the authority to order the use of those weapons.”
Noonan says that very determined opposition at the top levels of the Pentagon could at least slow a misguided use of nuclear weapons:
“There are two very important cogs in the machine. The first is the Chairman of the Joint Chiefs, and the second is the commander of United States Strategic Command. Without those two guys, without their compliance, it would be very difficult to bypass them. You need the mechanisms that they control in order to communicate with your subs, bombers and missiles.”
On the other hand, a president who was being obstructed in that way could start firing senior officers until he found one that would comply. The only real restraint would be wanting to avoid the spectacular controversy that would be involved.
There is some precedent for blunting a president’s nuclear authority. Toward the end of Richard Nixon’s presidency, then-defense secretary James Schlesinger ordered the Pentagon not to act on a nuclear launch order from the White House unless officers there had talked to him first.
“Nixon actually talked about how much power he had, that he could pick up the phone and order the use of nuclear weapons,” Blair explains. “He was making pretty strange comments about his nuclear power.”
“It was in the middle of Watergate, and he was on the brink of resignation, and depressed, and drinking heavily.”