Michael Gerhardt is the author of The Forgotten Presidents: Their Untold Constitutional Legacy ($34.95, OUP)
The 43 different men who have been president of the United States are not all equal. Americans revere and know a lot about only a few of these men. Yet, many presidents whom we have forgotten have had an impact on the office and the Constitution. In fact, the thirteen men, whom I deem the most forgotten, demonstrate that no one who serves as president, even for just a few weeks, has left the office or our Constitution untouched.