The James Madison class of submarine was an evolutionary development from the Lafayette class of fleet ballistic missile submarine. They were identical to the Lafayettes except for being designed to carry the Polaris A-3 missile instead of the earlier A-2. Then, in the early 1980s, they were further upgraded to carry the Trident C4 missile. Together with
the George Washington,
the Ethan Allen,
the Lafayette, and
the Benjamin Franklin
classes, they comprised the "41 for Freedom."