In February 1963, the United States Navy acquired ''Simmons Victory'' and converted her to a "Miscellaneous Auxiliary" ship at Williamette Iron and Steel of Portland, Oregon. On June 8, 1963, she was renamed Liberty and given hull classification symbol AG-168. On April 1, 1964, she was reclassified a Technical Research Ship (AGTR-5). She was commissioned at Puget Sound Naval Shipyard, Bremerton, Washington, in December 1964.
In February 1965, Liberty steamed from the west coast to Norfolk, Virginia, where she was further outfitted to suit her for a mission of supporting the National Security Agency by collecting and processing foreign communications and other electronic emissions of possible national defense interest.
In June 1965, Liberty began her first deployment, to waters off the west coast of Africa. She carried out several more operations during the next two years, and went to the Mediterranean Sea in 1967. During the Six-Day War between Israel and several Arab nations, she was sent to collect electronic intelligence in the eastern Mediterranean.
On the afternoon of June 8, 1967, while in international waters off the Sinai Peninsula, Liberty was attacked and damaged by Israeli forces; 34 crewmen were killed and 172 wounded. Considerable controversy surrounds this attack; please see Israeli attack on USS Liberty for details. Though severely damaged, Liberty’s crew kept her afloat, and she was able to leave the area under her own power. She was escorted to Malta by units of the U.S. Sixth Fleet and was there given interim repairs. After these were completed, Liberty returned to the United States, where she was immediately decommissioned and struck from the Naval Register on June 28, 1968. She was laid up in the Atlantic Reserve Fleet, Norfolk, Virginia until December 1970, when she was transferred to the Maritime Administration for disposal. In 1973 she was sold for scrapping.
USS Liberty was awarded the Presidential Unit Citation and Commander William McGonagle, Liberty’s commanding officer, received the Medal of Honor.