President Franklin Delano Roosevelt ended Prohibition, pulled the United States out of the Great Depression, and bolstered Allied Forces during World War II. He also suffered from paralysis, which was widely believed to have been caused by polio.

If 24 has taught us anything, it's that the presidential succession can be the stuff of riveting, wildly implausible drama. Here are five presidential might-have-beens that would make for some fascinating alternate history stories.