Tom Clancy SSN is based upon Tom Clancy SSN, an interactive submarine combat thriller available on CD-ROM.China has invaded the oil-rich Spratly Islands. The American response has been swift and deadly, resulting in the start of World War III. SSN: Strategies of Submarine Warfare presents 15 thrilling scenarios-fact-based mission profiles for Captain Bartholomew Mackenzie and the crew of the nuclear submarine the U.S.S. Cheyenne-stirring plots and characters, perfectly accurate details, and the chilling knowledge that these events could really happen.