Offutt Air Force Base, Nebraska (CNN) If Russia aimed a long range missile like the "Satan 2" it just tested or North Korea suddenly targeted the headquarters of the US nuclear arsenal, top commanders would have a small window to get to safety.

But the US is ready for such a scenario and the four-star general tasked with executing the US response to a nuclear strike would take to the air within minutes. He'd be able to carry out the President's orders and launch a nuclear attack in response from the safety of a specially equipped jet, known as the "Doomsday" plane.

"I have a certain amount of minutes to get on that plane and for that plane to get off and to a safe distance before a nuclear weapon went off here," John Hyten, the head of US Strategic Command, told CNN in an exclusive interview earlier this month from his headquarters at Offutt Air Force Base in eastern Nebraska.

At the base a countdown clock is always visible to Hyten telling him how many minutes away an incoming missile would be from impact, as well as how much time he has to be rushed from his underground battle deck to the surface and a vehicle that would whisk him to a nearby tarmac where the all-important plane would be waiting.

"The roads will open up on this base and I'll go beeline straight for the runway," Hyten said.

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