Defense

US to deploy nuclear-armed subs to South Korea in face of North’s missile threats

South Korean President Yoon Suk Yeol shakes hands with President Biden during an arrival ceremony for Yoon on the South Lawn of the White House in Washington, D.C., on Wednesday, April 26, 2023.

The United States will deploy nuclear-armed submarines to South Korea for the first time since the 1980s, according to a new agreement signed between the two countries on Wednesday. 

President Biden and South Korean President Yoon Suk Yeol met at the White House to sign the deal in a show of support to Seoul in the face of increasing nuclear threats from North Korea. Kim Jong Un’s regime has upped its pace of ballistic missile tests in the past several months. 

The key tenet of the deal, which is to dock the ballistic missile submarines in the peninsula country, will ensure any South Korean response to a North Korean nuclear attack could include U.S. nuclear weapons, Yoon said alongside Biden in the White House Rose Garden. 

Biden confirmed that any nuclear attack by Pyongyang “against the United States or its allies or partners is unacceptable and will result in the end of whatever regime were to take such an action.” 

Called the “Washington Declaration,” the plan will see the United States increase the number of weapons that dock at or visit South Korean ports temporarily, including nuclear-armed submarine and bomber planes, though no such assets will be deployed on the peninsula itself, Biden said. 


The move is a departure from how the two countries operated during the Cold War, when Washington had hundreds of nuclear warheads in South Korea full time. 

The declaration also seeks to improve joint training between the two militaries and better information-sharing and coordination in a nuclear response strategy should the North attack the South, Yoon said.   

“What the declaration means is that we’re going to make every effort to consult with our allies when it’s appropriate if any actions so call for it,” Biden said. “There’s even closer cooperation, closer consultation.” 

South Korea, in turn, would reaffirm its commitment to the Nuclear Nonproliferation Treaty (NPT), meant to prevent countries from gaining nuclear weapons. South Korea gave up its own nuclear program when it signed the treaty almost 50 years prior, but North Korea is not a signatory to the agreement. 

South Korea and North Korea technically have their own joint declaration, signed in 1991, that pledged that neither country would build, test, possess, store, deploy or use nuclear weapons.

Pyongyang, however, has repeatedly violated the agreement, and earlier this month launched a solid-fuel intercontinental ballistic missile, the country’s first. The missile, which moved easier and fired faster than those with liquid fuel, has set off fears that the country now possesses harder-to-detect weapons as it gives observers less warning of it being fired.  

North Korea has also reacted angrily to last month’s joint military exercises between the United States and South Korea — the largest in the Korean peninsula in five years — with Pyongyang warning that the drills could push tensions to the “brink of a nuclear war,” and firing at least one missile from a submarine in the Sea of Japan.  

In addition, U.S. and South Korean officials say North Korea is prepping for its first nuclear test since 2017.  

All combined, Pyongyang’s bluster has prompted Seoul to seek to keep nuclear weapons nearby.  

In his opening remarks, Biden said the two countries’ commitment to nuclear threat deterrence is particularly important in the face of such North Korean threats. 

Yoon’s state visit marks the first from a South Korean leader in 12 years. The trip also marks the Biden administration’s first state visit by a leader from the Indo-Pacific.