Before Ice StationEdit
Through unknown circumstances, Jack Walsh joined the United States Marine Corps, wherein he eventually became the captain of the USS Wasp. Walsh, not caring enough about politics to further his career, opted to remain captain of the Wasp, allowing him to become Harrier pilot Shane Schofield's commander.
After Schofield was shot down over Bosnia and needed to be rescued, Walsh disobeyed his superiors and ordered for a team of Marines to get him out. Though somewhat successful in retrieving Schofield, due to a large number of injuries sustained by the rescue team, Walsh's superiors weren't happy with his actions, but allowed him to continue captaining the Wasp.
After escaping the doomed Wilkes Ice Station in the B-7A Silhouette, Schofield learned that the Wasp was somewhere off the coast of Antartica, and landed on the Wasp with Elizabeth Gant, James Renshaw, Kirsty Hensleigh, and Wendy. Though greeted by Walsh himself, who noted that Schofield had been mentioned a lot in radio chatter, Clayton took charge of trying to examine the Silhouette with his own men. Schofield prematurely apologizes to Walsh about the deck of his ship, just as a missile slams into the plane, killing Clayton.
Walsh, after hearing Schofield's story about what was going on, forgives him for the damage and gives him and his fellow survivors a ride back to Pearl Harbour in Hawaii. After making port, Walsh recieved an urgent call about Schofield being in danger from the ICG by Andrew Trent. Walsh and some of his men surrounded Charles Kozlowski's car, and pulled rank on the ICG man, and had him arrested. Schofield thanked Walsh for saving him, though Walsh pointed out Trent as the one who notified him of the danger.