Police Action

An isolated undertaking, military in nature, intended to curb either an insurgency within a state's own borders or by one state against another when that state is in violation of international treaties or norms or is found to have engaged in an act of aggression. Under international and domestic laws, military action can be undertaken by a state either pursuant to a declaration of war against another state or as a police action. In the United States, the Constitution requires that a declaration of war against another state be approved [Page 582]by Congress. Absent a declaration of war, however, the president can order military action by virtue of his powers as commander in chief of the armed forces.

In terms of international law, police actions are permissible under two circumstances. Initiating military action against a state—thus infringing upon its political and territorial sovereignty—is permissible under international law only when that state has perpetrated an act of aggression against another state or when it has otherwise posed a threat to international peace and security and a collective decision has been made by the United Nations to curb this action. One other instance in which a police action is permissible is when a state acts in self-defense against imminent attack by another state, which is deemed the aggressor even if it has not yet attacked. In the post–Cold War era, these lines have been blurred to occasionally include the permission of territorial and political infringement upon states whose governments perpetrate atrocities against their own people, but this is a developing issue. In the post–September 11, 2001, era, these guidelines have become even murkier as states militarily pursue individuals they deem terrorists within the borders of other states.

Even before today's global issues challenged the parameters set up by the UN Charter and other instruments of international law, military activity between states never quite fit neatly within the framework set up by those treaties and pacts. That is, most military activity takes place outside of the context of a declaration of war.

In U.S. history, examples of such incidents abound and include the Korean War, the invasion of Grenada, the Gulf War of 1991, and U.S. involvement in the Balkan wars of the 1990s.

Arguably the most infamous police action undertaken by the United States is the Vietnam War. Like the Korean War, the Vietnam conflict was fueled by the tensions of the Cold War, and U.S. involvement in it was intended to curb the spread of communism in Southeast Asia. The conflict was prolonged far beyond initial expectations, snowballing and drawing the United States further and further into the quagmire, despite growing antiwar sentiment at home calling for extraction from the region.