Defense attaches are under the command of which of the following Defense Department units?

Defense attaches operate under the Defense Intelligence Agency (DIA). The primary function of defense attaches is to provide military expertise and analysis, facilitate communication between the U.S. military and foreign military entities, and contribute to intelligence gathering and security cooperation efforts. By being part of the DIA, these attaches can effectively perform their roles in support of national security and defense policies, as well as provide crucial insights into the military capabilities and intentions of foreign nations.

In terms of the roles of the other options, the Joint Chiefs of Staff focus on the strategic direction and management of U.S. military forces rather than direct engagement with foreign militaries. The Assistant Secretary for International Security Policy handles broader policy issues and international security measures but does not directly command military attaches. The Defense Security Cooperation Agency primarily deals with security assistance and arms sales but does not encompass the specific functions and command structures related to defense attaches in the foreign military context.