In 1951, at the height of the Cold War, the U.S. Army Chemical Corps and Ordnance Corps initiated a program to develop a new rocket that could deliver chemical weapons over a large area. The result was the M55 rocket, which was equipped with a unitary warhead filled with sarin or VX—highly toxic nerve agents. The rocket was rushed into production, and tens of thousands were produced from 1959 to 1965.
Thankfully, the rockets were never used. Decades later, in 1993, the United States signed the Chemical Weapons Convention, an international treaty that bans the use of chemical weapons and aims to eliminate them throughout the world. The country has been trying to dispose of its stockpiles ever since.