The threat or use of chemical, biological, radiological, or nuclear weapons by hostile regimes and terrorists represents one of the most difficult challenges facing our nation and our Air Force. This challenge is further complicated by the advance of technologies used to develop and deliver these weapons, making it possible for our enemies to attack us at a time and place of their choosing, with little or no warning. Success in defending our nation, our military forces, and partners and allies depends on how effectively we apply air, space, and cyberspace power to counter this threat.