The United States nuclear arsenal can go from standby to missile launch in about five minutes, according to Bruce Blair a former Minuteman launch control officer.
The U.S. Strategic Command uses a strict protocol to authorize a launch.
Launching the U.S. arsenal requires eight steps, according to Blair, a research scholar at Princeton University's program on science and global security and founder of nonproliferation advocacy group Global Zero.
The video above explains the protocols, but basically the president first talks to advisors such as the Omaha-based four-star general at the helm of the U.S. Strategic Command. The president's conclusion is then carried out through a series of codes and encrypted messages that travel through the Pentagon to the land- or sea-based launch sites, where control officers simultaneously turn their security keys to initiate the launch.
Tensions between North Korea and the United States reached new heights on Aug. 8, when President Donald Trump warned the rogue regime it faced "fire and fury" if it made any more threats. North Korea responded by saying it planned to test fire missiles in the waters off the U.S. Pacific territory of Guam. This week, Pyongyang toned down its rhetoric, saying it would wait to assess "the foolish and stupid conduct" of the United States.
North Korea test-fired a missile on July 28, despite pressure from China to abandon its nuclear weapons and ballistic missile programs. Following the launch, defense experts confirmed North Korea has the capability to reach more than half the continental U.S. with a nuclear-armed intercontinental ballistic missile.
U.S. intelligence believes North Korean leader Kim Jong Un has up to 60 nuclear weapons, though some independent experts say the total is smaller. By comparison, the U.S. has around 6,800 nuclear weapons, according to the Federation of American Scientists, with about 1,800 actively deployed at land bases and submarines.
Five states in the continental U.S. are home to missile launch sites: Colorado, Montana, Nebraska, North Dakota and Wyoming, according to the Congressional Research Service. The Eighth Air Force operates five nuclear-capable bomber wings out of bases in Louisiana, North Dakota, South Dakota, Missouri and Texas. There also are 14 active Ohio-class submarines, with four of the nuclear-armed ships on designated "hard alert" patrols at any time.