The Bureau of Political-Military Affairs (PM) is a true middle man. The bureau is the liaison between the Departments of State and Defense; it influences US policy related to defense strategy, defense trade, international security, military operations, military use of space, and security assistance. PM works on counterterrorism, regional stability, humanitarian response (including programs addressing land mines and natural disasters), and homeland security. The bureau operates through six main offices including ones for security negotiations, weapons removal, and regional security. The State Department's Under Secretary for Arms Control and International Security oversees PM.