If North Korea launched a nuclear missile at the U.S., here’s how it could play out

The tensions between North Korea and the United States continue to escalate after the rogue nation launched another intercontinental ballistic missile Wednesday.

North Korea claimed the new missile, which appears to be significantly bigger than one tested in July, could also hit any target in the United States.

And after it launched, U.S. Defense Secretary James Mattis said the missile demonstrated North Korea had the ability to hit “everywhere in the world.”

Dr. Bruce Blair, former nuclear launch officer and co-founder of Global Zero, said the crisis between the two countries is escalating and “bringing us to the brink of conflict.”

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It would take only half an hour for a North Korean missile to reach the U.S. And if it was targeted to hit the East Coast, it would surely fly over Canada, Blair said.

During this time, there would be a flurry of activity involving emergency meetings, making sure the president is safe and deciding whether to retaliate.

Here’s what it could look like:

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North Korea launches missile

The fiery hot plume of the booster would be detected within one minute by U.S. satellites equipped with heat detectors.

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This would spark the early stage of the U.S.’s missile defence and the nuclear retaliation protocols, according to Blair.

Missile defence units notified

Missile defence units in Alaska and California would be quickly notified. Allied countries, such as South Korea and Japan would also be briefed.

In order to detect where the missile is going, two ground radar sites in Alaska would detect and analyze the path.

“Once a rocket is launched it goes straight up for awhile so it’s hard to determine its flight path,” Blair said.

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The missile defence units would then prepare to launch their interceptors designed to hit the missile in the middle of its trajectory.

According to Blair, the interceptors have a 25 per cent chance of head-on collision with the attacking missile, but most experts believe the true performance to be much lower.

Emergency meeting

During the same time, an emergency conference would be held with the head of strategic command, the president and his top advisers.

If the path of the missile is targeting North America, the president would have a few minutes to decide if retaliation is needed.

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Before this decision is made, the U.S. military’s alert would be raised two notches to a level known as “Defence Condition Two.” Blair said the only other time this level has been reached was during the 1962 Cuban Missile Crisis.

U.S. forces would then prepare for retaliation and wait for a launch order.

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Emergency plans

During the emergency conference, two emergency plans would be initiated, according to Blair.

Emergency plan 1: Continuity of government

The purpose of this plan is to ensure the safety of the president and other key government leaders.

This plan has been used once on Sept. 11, 2001, when former U.S. president George W. Bush was whisked away to Air Force bases in Louisiana and Nebraska.

If the president was in the White House during the missile threat, he would only have a few minutes to get to the helicopter and fly to a rendezvous base outside of Washington. The president would then board the doomsday plane, a militarized Boeing 747 possessing all the launch codes and the communications gear needed to send orders directly to the submarines, underground missile crews and bomber crews.

Emergency plan 2: Civil defence

During this plan, the population would be warned of the missile strike by radio and television using a special tone.

From an evacuation site, the president would probably address the nation on available commercial and other channels such as the emergency broadcast network. Bush did this during 9/11.

The national guard and other protection and policing functions would be activated.

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