Traditionally, national security roles fall into five categories:
- Diplomatic: influencing foreign nations and international organizations through bi-lateral and multi-lateral agreements, negotiations, and engagement.
- Economic: shaping international activity through U.S. spending and taxation; policy on money supply and interest rates; sanctions; export controls; trade and investment agreements; development assistance and humanitarian relief; and leading by example through maintenance of openness to foreign trade, investment policy, and arrangements.
- Information: communicating U.S. Government intent, values, and views.
- Military: using the capabilities of the U.S. Armed Forces to deter conflict, defeat an adversary, or respond to a crisis.
- Intelligence: gathering and interpreting information relating to the capabilities, intentions, or activities of foreign governments, organizations, or persons, or international terrorist activities to support decision-making.
National security roles can also include financial and law enforcement issues, particularly for transnational threats, such as terrorism, counternarcotics, and proliferation of WMD. These lines of operation also provide critical feedback that should be factored into U.S. policy decisions and actions.
Key national security players from the Executive Branch include the President, National Security Council, Department of State, U.S. Agency for International Development, Department of Defense, Intelligence Community, Department of Commerce, and Department of the Treasury. Increasingly, agencies not traditionally considered as "national security agencies," such as the Departments of Agriculture and/or Interior, perform roles that have national security implications. The Department of Homeland Security (DHS), although domestically focused, interacts internationally for domestic security purposes (for example, through engagement between DHS components, such as U.S. Customs and Border Protection, and foreign counterparts to address security issues before cargo originating overseas reaches the United States).