As our 27th president from 1909 to 1913, and then as chief justice of the Supreme Court from 1921 to 1930, William Howard Taft was the only man ever to lead two of America's three governing branches. But between these two well-documented periods in office, there lies an eight-year patch of largely unexplored political wilderness. It was during this time, after all, that Taft somehow managed to rise from his ignominious defeat by both Woodrow Wilson...