What does the Reaffirming Extended Nuclear Deterrence Act require the United States to do for South Korea?

The bill calls on Washington to reaffirm that its extended-deterrence commitments to South Korea and other treaty allies remain ironclad. It supports maintaining a credible nuclear deterrent through conventional military capabilities, joint exercises, strategic consultations and defense investments.

Why did Mark Kelly and Thom Tillis introduce the nuclear deterrence bill now?

The senators cited growing nuclear threats from North Korea, China and Russia. They also acted after urging the Trump administration to reverse a decision to substantially reduce joint military exercises with South Korea, with Kelly warning that confusing allies could weaken deterrence.

Bipartisan US Senate bill reaffirms 'ironclad' nuclear deterrence pledge to S. Korea

Q: Which countries and organizations are covered by the US extended nuclear deterrence legislation?

The legislation specifically names South Korea, Japan, Australia and members of NATO as treaty allies whose security directly advances U.S. national security interests. It also highlights the nuclear challenges posed by North Korea, China and Russia.

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Summary

Two U.S. senators introduced bipartisan legislation in Washington late last month to reaffirm the United States’ “ironclad” extended nuclear deterrence commitment to South Korea and other treaty allies. The Reaffirming Extended Nuclear Deterrence Act calls for a credible nuclear deterrent backed by conventional forces, joint exercises and strategic consultations. It identifies South Korea, Japan, Australia and NATO members as allies whose security advances U.S. national interests amid nuclear threats from North Korea, China and Russia.

Key Facts

The bill was introduced by Sen. Mark Kelly, a Democrat from Arizona, and cosponsored by Sen. Thom Tillis, a Republican from North Carolina.
The legislation says U.S. military posture, exercises, strategic consultations and defense investments should demonstrate continued extended-deterrence commitments.
The bill says sustained consultations, planning and military exercises can strengthen collective readiness and have helped discourage allies from developing independent nuclear weapons.
Kelly and Tillis introduced the legislation after urging the Trump administration to reverse its decision to substantially reduce joint military exercises with South Korea.

By Yonhap

Published Oct 16, 2026 3:05 am KST

The U.S. Capitol, as viewed from the National Mall, at blue hour in Washington, D.C., Sept. 1. Reuters-Yonhap

WASHINGTON — Two U.S. senators have introduced bipartisan legislation seeking to reaffirm Washington's "ironclad" extended nuclear deterrence commitments to South Korea and other treaty allies, amid growing nuclear threats from North Korea, China and Russia.

The Reaffirming Extended Nuclear Deterrence Act, introduced by Sen. Mark Kelly (D-AZ) late last month and cosponsored by Sen. Thom Tillis (R-NC), calls for maintaining a credible U.S. nuclear deterrent supported by conventional military capabilities, joint exercises and strategic consultations with allies.

The bill states that United States should "reaffirm that its extended deterrence commitments to its treaty allies remain ironclad" and ensure that its military posture, exercises, strategic consultations and defense investments demonstrate

The legislation specifically identifies South Korea, Japan, Australia and members of the North Atlantic Treaty Organization (NATO) as allies whose security directly advances U.S. national security interests, while highlighting growing nuclear threats from North Korea, China and Russia.

It also underscores the importance of sustained consultations, planning and military exercises with allies to strengthen collective readiness, noting that U.S. extended nuclear deterrence has helped discourage allies from developing independent nuclear weapons.

The legislation comes after Kelly and Tillis urged the Trump administration to reverse its decision to substantially reduce joint military exercises with South Korea.

"Deterrence only works if adversaries believe you mean it. China and Russia are expanding their nuclear arsenals. North Korea keeps pushing. This is the wrong moment to leave allies confused about where we stand," Kelly said in a statement announcing the legislation.

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