Walter Gahagan had a law degree from Columbia University and worked from 1939-41 as an assistant United States Attorney in New York. He later took over his father’s dredging company, which moved from New York City to Tampa. With that company Gahagan was involved in the construction of the launch pad for the Apollo spacecrafts and the John F. Kennedy airport in New York. His sister Helen Gahagan Douglas was an actress and politician, who served three terms (1945-51) as a Congresswoman from California and lost the 1950 Senate race to Richard Nixon.