W88

The W88 is an American thermonuclear warhead with an estimated yield of 475 kilotons, small enough to be carried on missiles fitted with multiple independently targetable reentry vehicles. It was designed at the Los Alamos National Laboratory in the 1970s and entered service in 1989; the laboratory director who oversaw its development described it as the most advanced United States nuclear warhead of its time. The Trident II submarine-launched ballistic missile can carry up to eight W88 warheads. A later version, the W88 ALT 370, began production on 1 July 2021 after eleven years of development, and the W88 is expected to become the highest-yield warhead in the United States arsenal once the B83 nuclear bomb is retired.