The Nuclear First-Strike Security Act of 2025

This bill would limit the government from spending money to carry out a first-use nuclear strike unless two things happen: the President decides it’s in the best interest of the United States, and the Secretary of Defense certifies to congressional leaders—no more than 7 days before the strike—that the decision is valid and legal. It makes clear this rule does not apply if Congress has declared war, if the U.S. or a listed ally has already been hit by a nuclear attack, or in a “launch-on-warning” situation where U.S. systems detect an incoming missile aimed at the U.S. or an ally.

Allies named include NATO countries, Japan, South Korea, and Australia. A “first-use nuclear strike” means using nuclear weapons when the Defense Secretary and the Chairman of the Joint Chiefs have not jointly confirmed the other country already carried out a nuclear attack on the U.S. or an ally. A “nuclear attack” means one or more nuclear detonations on U.S. or allied soil.

• Who is affected: The President, the Department of Defense, Congress, and U.S. allies (NATO, Japan, South Korea, Australia).
• What changes: Federal funds cannot be used for a first-use nuclear strike without a presidential decision plus a Defense Secretary certification within 7 days, except in war, after a nuclear attack, or during launch-on-warning.
• Why it matters: Adds a check before any first-use of nuclear weapons, while still allowing rapid response if the U.S. or an ally is under nuclear threat or attack.