U.S. Coast Guard | 123,974 followers on LinkedIn. The official LinkedIn for the U.S. Coast Guard | The mission of the U.S. Coast Guard is to protect the public, the environment, and U.S. economic interests — along the coast and our coastal borders, in the nation's ports and waterways, in international waters, or in any maritime region as required to support national security. As one of the six branches of the Armed Forces, the U.S.