And if there is a nuclear weapon barrelling towards the U.S., the president may have only minutes to make a world-changing decision. And the U.S. Senate, House of Representatives and Supreme Court don’t have a say in it.
The immediacy to launch an attack stems from the Cold War logic that still governs the system — a nuclear enemy (such as North Korea) has to be assured that a retaliatory strike can be ordered instantly. So if U.S. President Donald Trump takes too long to debate, or reflect on his decision, it could lead to obliteration.
WATCH: President Trump threatens to “totally destroy North Korea”
There isn’t a “button” the president presses to launch a nuclear attack. There are steps involved, but ultimately the president is the sole decision maker.
“People can question him, but at some point, he picks up the call for the war room and no one in the line of command can stop it,” David Wright co-director of the UCS Global Security Program said.
1. President opens a ‘nuclear football’
The president will first open the “nuclear football.” This black briefcase is said to contain an outline of nuclear attack options and instructions for contacting U.S. military commanders around the world to give the order to launch missiles.
The president is always accompanied by a military aide carrying the briefcase with launch codes for nuclear weapons, according to the Smithsonian.
“The Football also provides the commander in chief with a simplified menu of nuclear strike options—allowing him to decide, for example, whether to destroy all of America’s enemies in one fell swoop or to limit himself to obliterating only Moscow or Pyongyang or Beijing,” the Smithsonian stated.
2. President has a conversation with top military officers
Although the president has the ultimate say when it comes to launching a nuclear attack, he/she is supposed to discuss the attack options with military officers.
This includes an officer in charge of the National Military Command Center, or “war room” and the head of the U.S. Strategic Command. The conversation can be done in-person or over the phone.
WATCH: Donald Trump looking to expand nuclear arsenals
3. President makes a decision and the order is given
The decision to launch a nuclear attack may take mere seconds. Some advisers may try to change the president’s mind, but the Pentagon has to comply with the commander-in-chief’s order.
The senior officer in the Pentagon’s war room then reads a “challenge code” to verify the order is coming from the president (it’s usually two phonetic letters from the military alphabet). The president is then given a laminated card called “the biscuit” and finds the matching response to the challenge code. If it’s the correct response, the order passes down the chain of command.
4. Launch crews prepare to attack
The war room will send a launch order to the submarine, air and ground crews. This is an encrypted message with sealed authentication system (SA) and missile unlock codes.
If launching a missile from a submarine, the captain, executive officer and two other crew members authenticate the order using the codes provided. The launch order contains the combination for another safe, which has the keys needed to fire the missiles.
Ground crews have a slightly different procedure. The launch order goes to five crews spread across the U.S., each with two officers. Each squadron has around 50 missiles. At launch time, all crews simultaneously turn their launch keys to fire missiles. Only two crews in each group must turn their keys in order for a missile to launch.
5. Missiles are launched
Land-based missiles can be on their way within five minutes and for submarines around 15 minutes. Once the missiles are launched they cannot be called back.
If the president orders a misguided or inappropriate use of nuclear weapons, there is little to stop it from being carried out, according to Princeton University professor Bruce Blair, who is also a former nuclear launch officer.
Officers could refuse to pull the trigger on the attack (but of course risk breaking the law and being thrown in prison). According to Blair, the nuclear launch system is designed to survive being attacked and also to carry out a launch order with extreme speed and little questioning.
“(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.”
WATCH: Russian officer credited for averting nuclear war passes away
The method was designed for a very rapid reaction, and “there are very few checks and balances that can be imposed on that kind of timeline,” Blair said.
Because of this, two Democrats in the U.S. Congress attempted to pass a bill in January that would restrict the president’s authority to use nuclear weapons with a declaration of war by Congress. The bill has not been passed.
In 1979, when Jimmy Carter was president, his national security adviser, Zbigniew Brzezinski, received back-to-back calls in the middle of the night informing him of the imminent nuclear destruction of the United States.
Brzezinski was apparently seconds away from calling Carter to convince him to immediately retaliate. However, just before he picked up the phone, he received a third call, this time cancelling the alarm. The false alarm was later traced to a faulty computer chip that malfunctioned and had sent the signal that 2,000 Soviet Union missiles were on their way.
Another close call was toward the end of Richard Nixon’s presidency in 1974. His then-defence 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. This was because Nixon’s mental stability and heavy drinking caused concern within his inner circle.
“Nixon actually talked about how much power he had, that he could pick up the phone and order the use of nuclear weapons,” Blair said. “He was making pretty strange comments about his nuclear power.”
There have been a number of false alarms over the years and people have almost launched nuclear weapons based on false data, Wright said. And if you have a commander in chief who is impulsive and not giving a good decision, “then you have a system that is prone to failure,” he added.
“How long can this current system go forward until some screw up happens?”
— With files from Global News’ Patrick Cain
© 2017 Global News, a division of Corus Entertainment Inc.