The 455th Chemical Brigade is a specialized unit within the United States Army, primarily responsible for chemical defense and defense against weapons of mass destruction. It falls under the umbrella of the Army's Chemical, Biological, Radiological, and Nuclear (CBRN) defense forces. The brigade's main mission is to protect troops, civilian populations, and critical infrastructure from harmful chemical, biological, radiological, and nuclear threats. The 455th Chemical Brigade operates under the U.S. Army Chemical School at Fort Leonard Wood, Missouri. Throughout its history, the unit has participated in various domestic and international operations, demonstrating its crucial role in ensuring the safety of forces and communities.