USS Loyalty (AM-457/MSO-457) was an Aggressive-class minesweeper acquired by the U.S. Navy for the task of removing mines that had been placed in the water to prevent the safe passage of ships.

From 1956 until late 1964 Loyalty sailed on three WestPac cruises; performed special operations in 1962 during the nuclear tests in the Pacific Ocean; and exercised off the California coast perfecting the techniques of modern mine warfare.

Following the Gulf of Tonkin incident when North Vietnamese torpedo boats attacked U.S. destroyers in international waters, Loyalty was dispatched to steam off the coast of Vietnam ready for further provocation.

Loyalty continued as a unit of task force TF 115 through late 1968, stopping only briefly for respites in Subic Bay or Hong Kong and overhauls in her home port, Long Beach, California.

In November 1970, Loyalty returned to the Western Pacific and Operation Market Time, Performing radar picket, as well as search and seizure duties in Viet Nam.