Part of the current effort to maintain a viable U.S. nuclear deterrent is the development of a warhead dubbed the W93, the request for which was first introduced in the President’s 2021 budget request. The W93, along with its Mark 7 (Mk7) re-entry vehicle that holds the warhead, will replace W76 and W88 warheads found atop the Navy’s Trident II D5 submarine-launched ballistic missiles (SLBMs) with a safer design.