USS Decatur (DD-936)
 See USS Decatur for other ships of the same name.The fourth USS Decatur (DD-936) was a Forrest Sherman-class destroyer of the United States Navy in service from 1956 to 1983. She was named for Commodore Stephen Decatur USN (1779–1820). Decatur was modernised as a guided missile destroyer in the mid-1960s and re-designated DDG-31. After her decommissioning in 1983 she operated as the U.S. Navy's Self Defense Test Ship from 1994 to 2003. She was finally sunk as a target the following year.