Underwater Demolition Teams had a specialized non-tactical mission when the United States Navy created them during World War II. Postwar they transitioned to scuba gear changing their capabilities. With that they came to be considered more elite and tactical during the Korean and Vietnam Wars. Their primary WWII function began with reconnaissance and underwater demolition of natural or man-made obstacles obstructing amphibious landings. UDTs were pioneers in underwater demolition, closed-circuit diving, combat swimming, and midget submarine operations. Commando training was added making them the forerunner to the United States Navy SEAL program that exists today.