Jim Mulligan was born in 1926 in Lawrence, Massachusetts. He enlisted in the Naval Aviation Cadet V-5 Program on February 6, 1944, and was commissioned an Ensign in the U.S. Navy and designated a Naval Aviator on August 16, 1947. After completing transition training in the AD Skyraider, Ens Mulligan served as an AD-3 and AD-4 Skyraider pilot with VA-8A and VA-75 at NAS Oceana, Virginia, from April 1948 to November 1949, followed by service in the Naval Reserve with VF-913 at Squantum, Massachusetts, from November 1949 until he was reactivated in July 1950. He then served as an AD-3W pilot with VC-12 at Quonset Point, Rhode Island, from August 1950 until leaving active duty in August 1952. LtJg Mulligan re-joined the Naval Reserve in January 1953, serving with VF-917 at South Weymouth, Massachusetts, until returning to active duty in January 1956. LCDR Mulligan next served as a flight instructor at NAS Pensacola, Florida, from January 1956 to January 1959, followed by service as an A4D Skyhawk flight instructor with VF-21 and VA-43, the A4D Replacement Air Group, at NAS Oceana, Virginia, from January 1959 to November 1960. His next assignment was as an A-4 pilot and Operations Officer with VA-72 at NAS Oceana from November 1960 to December 1962, and then as a staff officer on the staff of the Chief of Naval Operations in the Pentagon from January 1963 to July 1964. CDR Mulligan attended Armed Forces Staff College from July 1964 to January 1965, and then was Executive Officer of VA-36 aboard the aircraft carrier USS Enterprise (CVN-65) deployed to Southeast Asia from January 1965 until he was forced to eject over North Vietnam and was taken as a Prisoner of War on March 20, 1966. He was to have become Commanding Officer of the Squadron on April 1. After spending 2,522 days in captivity, Capt Mulligan was released during Operation Homecoming on February 12, 1973. He was briefly hospitalized at the Naval Hospital in Portsmouth, Virginia, and then attended Old Dominion University in Norfolk, Virginia, from May 1974 until his retirement from the Navy on August 1, 1975.

His 2nd Silver Star Citation reads:

For conspicuous gallantry and intrepidity while interned as a Prisoner of War in North Vietnam. In January 1969, his captors, completely ignoring international agreements, subjected him to extreme mental and physical cruelties in an attempt to obtain military information and false confessions for propaganda purposes. Through his resistance to those brutalities, he contributed significantly toward the eventual abandonment of harsh treatment by the North Vietnamese, which was attacking international attention. By his determination, courage, resourcefulness, and devotion to duty, he reflected great credit upon himself and upheld the highest traditions of the Naval Service and the United States Armed Forces.