United States Coast Guard

The United States Coast Guard (USCG) is at all times a branch of the U.S. military, a maritime law enforcement agency, and a federal regulatory body. The Coast Guard has eleven statutory missions: Migrant Interdiction, Defense Readiness, Drug Interdiction, Ports, Waterways and Coastal Security, Other Law Enforcement, Search and Rescue, Aids to Navigation, Marine Safety, Living Marine Resources, Marine Environmental Protection, and Ice Operations. As one of the seven uniformed services of the United States, and the smallest armed service of the United States, its stated mission is to protect the public, the environment, and the United States economic and security interests in any maritime region in which those interests may be at risk, including international waters and America's coasts, ports, and inland waterways.
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Noun
1. an agency of the Department of Transportation responsible for patrolling shores and facilitating nautical commerce
(synonym) U. S. Coast Guard, US Coast Guard
(hypernym) coastguard
(part-holonym) Department of Transportation, Transportation, DoT

Established by act of January 28, 1915 (14 U.S.C. 1), became a component of the Department of Transportation on April 1, 1967, pursuant to the Department of Transportation Act of October 15, 1966 (49 U.S.C. app. 1651 note). The Coast Guard is a branch of the Armed Forces of the United States at all times and is a service within the Department of Transportation except when operating as part of the Navy in time of war or when the President directs. The predecessor of the Coast Guard, the Revenue Marine was established in 1790 as a federal maritime law enforcement agency. Other responsibilities include: search and rescue, maritime law enforcement, marine inspection, marine licensing, Great Lakes pilotage, marine environmental response, port safety and security, waterways management, aids to navigation, bridge administration, ice operations, deepwater ports, boating safety, Coast Guard auxiliary, military readiness, reserve training and Marine Safety Council. (OFR1)