Recent advances in North Korea’s nuclear and missile programs have led to speculations about the possible redeployment of U.S. nuclear weapons on the Korean Peninsula. The United States deployed nuclear weapons on the Korean Peninsula between 1958 and 1991. The only warheads remaining in the U.S. stockpile that could be deployed on the Korean Peninsula are B61 bombs. Before redeploying these to South Korea, where they would remain under U.S. control, the United States would have to recreate the infrastructure needed to house the bombs and would also have to train and certify the personnel responsible for maintaining the weapons and operating the aircraft for the nuclear mission.
Redeployment of U.S. nuclear weapons has the following advantages :
Send a powerful deterrent message to the North and demonstrate a strong commitment to the South
Weapons could serve as a “bargaining chip” with North Korea
Presence of nuclear weapons would allow for a more rapid nuclear response to a North Korean attack.
DISADVANTAGES
The weapons would present a tempting target for North Korea and might prompt an attack early in a crisis
Nuclear weapons based in the United States are sufficient for deterrence
It is not cost effective
South Korea’s President Moon Jae-in has advocated for more muscular defense options, but does not support the redeployment of U.S. tactical nuclear weapons.
China
Likely to view the redeployment of U.S. nuclear weapons as provocative;
Might respond by putting more pressure on North Korea to slow its programs,
Might increase its support for North Korea in the face of a new threat and, possibly, expand its own nuclear arsenal
Japan
Reaction could also be mixed.
Japan shares U.S. and South Korean concerns about the threat from North Korea, but given its historical aversion to nuclear weapons, Japan could oppose the presence of U.S. nuclear weapons near its territory.
Any adjustment of the U.S. military posture on the peninsula could create additional security concerns for Tokyo.
USA is conducting a Nuclear Posture Review that is examining both the role of nuclear weapons in U.S. national security policy and ongoing plans to modernize the U.S. nuclear enterprise.It is considering increased deployments of U.S. nonnuclear strategic assets to South Korea, changes in military exercises and the expansion of U.S.-ROK consultation strategic consultations
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