Ultimately the purpose of the USS Growler was as a nuclear deterrent. To this end she carried the Regulus Cruise Missile SSM-N-8, an unmanned turbojet powered vehicle system was capable of delivering a thermonuclear warhead within a range of 500 nautical miles.
A legacy of the German V1 rocket, the Regulus program ushered in a new era that changed the strategic role of the submarine forever. Developed by the Navy and Chance Vought Aircraft, the missile was carried horizontally in a chamber on top of the sub. To fire the sub would have to surface. The missile was then rolled out, positioned and fired.
All but forgotten, today the Regulus is a historical footnote to its successors that could be launched submerged. Regulus was critical in the development of today's sophisticated Tomahawk cruise missile, and served as an important nuclear deterrent in the early days of the Cold War and during the Cuban Missile Crisis.
