In 2261, Kawagawa was in command of the EAS Nemesis and ordered to be part of a blockade of Proxima III. Despite orders from President Morgan Clark to use lethal force against any civilians attempting to run the blockade, Captain Kawagawa went to great lengths to avoid firing on civilian targets.
Captain John Sheridan of Babylon 5 lead a fleet of White Stars to lift the blockade, culminating in the Battle of Proxima III. The Nemesis stayed out of the battle as long as it could, then quickly surrendered. Following the battle, Captain Sheridan had a meeting with Kawagaga and the other commanding officers of the surviving Earthforce ships. He offered to let them join his resistance. Kawagaga and his crew signed on and joined the task force that would eventually liberate Earth.