Formed under the U.S. Department of the Treasury in 1915, following the merger of the Revenue Cutter Service and the U.S. Life-Saving Service, the United States Coast Guard is one of the 5 branches of the United States Armed Forces. The USCG is a maritime, military, multi-mission service unique among the U.S. military branches for having a maritime law enforcement mission with jurisdiction in both domestic and international waters, and as a federal regulatory agency. Now operating under the U.S. Department of Homeland Security during peacetime, it can be transferred at any time to the U.S. Department of the Navy by the U.S. President, or by the U.S. Congress during times of war, as previously happened during both World Wars.
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