How the President can really launch a nuclear strike

President Donald Trump tweeted Jan. 2 that he had a "Nuclear Button" to launch a missile attack — but the process is much more complicated than the President made it seem.

Trump's tweet was a direct response to North Korean leader Kim Jong Un, who recently warned that nowhere in the U.S. is safe from his country's nuclear missiles. Despite warnings from the international community, Kim said, North Korea would produce as many missiles and nuclear weapons as possible.

"The entire United States is within range of our nuclear weapons, a nuclear button is always on my desk. This is reality, not a threat," Kim said during his New Year's speech. "This year, we should focus on mass-producing nuclear warheads and ballistic missiles for operational deployment. These weapons will be used only if our society is threatened."

Trump responded, tweeting, "North Korean Leader Kim Jong Un just stated that the 'Nuclear Button is on his desk at all times.'"

Read More: POTUS and North Korea exchange nuclear threats

"Will someone from his depleted and food starved regime please inform him that I too have a Nuclear Button, but it is a much bigger more powerful one than his, and my Button works!" Trump tweeted.

North Korean Leader Kim Jong Un just stated that the "Nuclear Button is on his desk at all times." Will someone from his depleted and food starved regime please inform him that I too have a Nuclear Button, but it is a much bigger more powerful one than his, and my Button works!

— Donald J. Trump (@realDonaldTrump) January 3, 2018

The President does not have a nuclear button, and the process of launching a nuclear missile is not as simple as, for example, pressing a button on a desk.

"U.S. nuclear forces operate under strict civilian control," retired Air Force general C. Robert Kehler, the former commander of U.S. Air Force Space Command as well as U.S. Strategic Command, recently said at a Senate Foreign Relations Committee hearing on nuclear weapons authority.

"The President's ability to exercise that ability and direction is ensured by people, processes, and capabilities that comprise the nuclear command and control system," Kehler said. "This is a system controlled by human beings — nothing happens automatically."

In short, there is no button.

Inside the 'football' and the 'biscuit'

It would be more accurate to say that there is a phone, and a long line of advisors, both civilian and military, that present all the facts and all the options on the table.

Once the decision is made, the President himself must authenticate that he is the one giving the order by calling the senior officer in the Pentagon. That officer will give the President a "challenge code" that requires a matching response, which the President or one of his aids carries at all time on a laminated card called the "biscuit."

Once the order is confirmed by the highest ranking official, it works its way down the chain of command until it reaches those who are responsible for turning the keys and carrying out the action.

The missile could be launched from either the sea or from land. In both cases, multiple people need to authenticate the order even after it comes down from the Pentagon.

Bloomberg determined that the process could take anywhere from five to 15 minutes after the President's order.

Even the famous "nuclear football" that is in reach of the President at all times does not contain a button.

Instead, it contains books with strike options, classified sites to shelter the President, instructions, codes, and likely some type of communication device.

Though the President has the authority to launch nuclear weapons, a press of a button on his desk will not send ICBMs hurling towards targets.

"The nuclear decision process includes assessment, review, and consultation between the president and key civilian and military leaders, followed by transmission and implementation of any presidential decision by the forces themselves" Kehler said.

"All activity surrounding nuclear weapons are characterized by layers of safeguards, tests, and reviews."