As flagship of Destroyer Squadron 3, "Joseph Strauss" sailed from Long Beach on 30 June 1964. After calling at Pearl Harbor and Midway Atoll, she arrived in Yokosuka, Japan on 18 July. While in port at Yokosuka, the crew of "Joseph Strauss" learned that North Vietnamese torpedo boats had attacked the U.S. destroyer in the Tonkin Gulf, and the ship hurried out of port with other squadron ships to join carrier forces in the South China Sea. She departed 3 August 1964 to rendezvous off Okinawa on 6 August with the aircraft carrier . During this time, U.S. Naval aircraft from "Constellation" conducted air strikes over North Vietnam. She then patrolled off the Vietnam coast and the South China Sea with task forces built around "Constellation", and . Brief sweeps were made to the Philippines and ports of Japan. "Joseph Strauss" arrived in Yokosuka on 15 December 1964 for upkeep, sailing again on 21 January 1965 to support U.S. Forces in Vietnam until 1 March. During this period, she operated with , , , and .