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Here are the types of information that are classified:
military plans, weapons systems, or operations; foreign government information; intelligence activities, sources, or methods, or cryptology; foreign relations or foreign activities of the United States, including confidential sources; scientific, technological or economic matters relating to national security, which includes defense against transnational terrorism; United States Government programs for safeguarding nuclear materials or facilities; vulnerabilities or capabilities of systems, installations, infrastructures, projects or plans, or protection services relating to the national security, which includes defense against transnational terrorism; the development, production, or use of weapons of mass destruction. |
