SAN DIEGO (May 15, 2020) -- Hospital ship USNS Mercy (T-AH 19) arrives in San Diego May 15. Mercy deployed in support of the nation's COVID-19 response efforts, and served as a referral hospital for non-COVID-19 patients admitted to shore-based hospitals. This allowed shore-based hospitals to focus their efforts on COVID-19 cases. One of the Department of Defense's missions is Defense Support of Civil Authorities. DoD is supporting the Federal Emergency Management Agency, the lead federal agency, as well as state, local and public health authorities in helping protect the health and safety of the American people. (U.S. Navy photo by Mass Communication Specialist 3rd Class Tim Heaps)