This bill restricts the use of funds for conducting first-use nuclear strikes , mandating a Presidential decision that such a strike is in the best interests of the United States. It further requires the Secretary of Defense to submit a certification to key Congressional leaders, confirming the decision's validity and legality, at least seven days before the strike. This seven-day certification is waived under specific exceptions, including a Congressional declaration of war, a response to a nuclear attack against the U.S. or an ally, or during a launch-on-warning scenario . A "first-use nuclear strike" is defined as one where the foreign country has not already conducted a nuclear attack against the United States or an ally, which includes NATO members, Japan, South Korea, and Australia. The legislation aims to establish a procedural check on the President's authority to initiate nuclear warfare without prior confirmation of an enemy nuclear strike, while still allowing for immediate response in critical defensive situations.