What is the Job of the US Coast Guard?

The United States Coast Guard is a naval component of the US Department of Defense, but their emphasis is far more on domestic obligations rather than battle.Now they can be mobilized for battle in scenario of war but their main precedence is to patrol the coastlines close to the United States, and aid citizens that need to have assistanceon the high seas.They are also a must have in policing the coastal waters and drug interdiction.
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