The new $716 billion defense authorization report has authorized $65 million towards the development of a new submarine-launched low-yield, “tactical” nuclear weapon. The specifics of the weapon have been a part of the administrations recent Nuclear Posture Review. Congress will still maintain its authority to authorize or prevent the development or modification of future nuclear warheads, which prevents the the secretary of energy (or anybody else) from imitating any phase of the development or production of nuclear warheads. Opponents of “tactical” nuclear warheads see the as decreasing the threshold for nuclear conflict.
Source: Tactical nuclear weapon launches into development with Pentagon policy bill