; or (2) reducing, or preparing to reduce, the quantity of deployed intercontinental ballistic missiles of the United States to a number less than 400. (b) Exception The prohibition in subsection (a) shall not apply to any of the following activities: (1) The maintenance or sustainment of intercontinental ballistic missiles. (2) Ensuring the safety, security, or reliability of intercontinental ballistic missiles. 1665. Briefing on long-range standoff weapon and sea-launched cruise missile Not later than 90 days after the date of the enactment of this Act, the Under Secretary of Defense for Acquisition and Sustainment, in consultation with the Administrator for Nuclear Security, shall provide to the Committees on Armed Services of the Senate and the House of Representatives a briefing on opportunities— (1) to increase commonality between the long-range standoff weapon and the sea-launched cruise missile; and (2) to leverage, in the development of the sea-launched cruise missile, technologies developed, or under development as of the date of the briefing, as part of the long-range standoff weapon program. 1666. Sense of the Senate on industrial base for Ground-Based Strategic Deterrent program It is the sense of the Senate that— (1) ensuring the viability of an industrial base of at least two domestic producers of large solid rocket motors for the ground-based strategic deterrent program is an important national security interest; and (2) in continuing to carry out that program, the Secretary of Defense should— (A) strive to maintain competition and proper vendor capabilities in order to maintain the best value for the Government; (B) consider the long-term health and viability of the industrial base when structuring and awarding major procurement or development contracts