Defense agencies are government organizations responsible for ensuring national security and protecting a country from external threats. They develop and implement defense policies, manage military operations, and oversee intelligence activities. These agencies often collaborate with other branches of the military and intelligence communities to maintain a comprehensive defense strategy. In many countries, defense agencies are tasked with research and development of advanced technologies, such as cybersecurity measures and military equipment. They also provide support during emergencies, such as natural disasters, by coordinating with local authorities and other government entities to ensure public safety and security.