Irregular warfare
Irregular warfare (IW) is defined in United States joint doctrine as "a violent struggle among state and non-state actors for legitimacy and influence over the relevant populations" and in U.S. law as "Department of Defense activities not involving armed conflict that support predetermined United States policy and military objectives conducted by, with, and through regular forces, irregular forces, groups, and individuals." In practice, control of institutions and infrastructure is also important. Concepts associated with irregular warfare are older than the term itself.