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Nuclear Triad Important to America's National Security

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The United States' strategic nuclear arsenal has been based on the nuclear triad system since the 1960s. The triad refers to the three categories of nuclear delivery vehicles: land-based intercontinental ballistic missiles, submarine-launched ballistic missiles and strategic aerial bombers.

Airmen stand beside large network devices
Airmen Inspection
Airmen from the 742nd Missile Squadron perform an inspection of the intercontinental ballistic missile system at Minot Air Force Base, N.D., Jan. 15, 2019.
Photo By: Air Force Senior Airman Jonathan McElderry
VIRIN: 190115-F-IY281-0022C
Submarine at sea
Sea Submarine
The Ohio-class ballistic missile submarine USS Louisiana transits the Hood Canal in Puget Sound, Wash., Oct. 15, 2017, as it returns to its homeport following a strategic deterrent patrol.
Photo By: Navy Lt. Cmdr. Michael Smith
VIRIN: 171015-N-TC277-269C
Jet flies over farmland
Bomber Flight
A B-52H Stratofortress nuclear-capable bomber flies over an undisclosed area.
Photo By: Air Force Senior Airman Luke Hill
VIRIN: 190422-F-PQ438-012C

Why It's Important

The purpose of the nuclear triad is to reduce the possibility that an enemy could destroy all the nation's nuclear forces in a first-strike attack by retaining a second-strike capability — a viable threat that increases nuclear deterrence. This would, in effect, make a successful first strike impossible.

Nuclear Posture Review

In 2018, the Pentagon released its Nuclear Posture Review. It noted that, while the U.S. has continued to reduce the number and salience of nuclear weapons, others, including Russia and China, have moved in the opposite direction. "They have added new types of nuclear capabilities to their arsenals, increased the salience of nuclear forces in their strategies and plans, and engaged in increasingly aggressive behavior, including in outer space and cyberspace."

Missile launches into sky
Engagement Test
Two long-range ground-based interceptor missiles are launched from Vandenberg Air Force Base, Calif., March 25, 2019, in the first-ever salvo engagement test of a threat-representative intercontinental ballistic missile target.
Photo By: Lisa Simunaci, DOD
VIRIN: 190325-D-AD122-002C

The review addressed the challenges posed by these nations and others and presents a roadmap for strengthening nuclear deterrent that includes modernizing systems, assurance of allies and partners and the achievement of U.S. national security objectives if deterrence fails.

Click here to read more about what David J. Trachtenberg, deputy undersecretary of defense for policy, had to say about America's nuclear posture at the Brookings Institution today in Washington.

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