The author, Jonathan Alter, Newsweek's senior editor, focuses on the seven and half months between Franklin D. Roosevelt's election as president and the end of the special session of Congress that became known as the "Hundred Days." Unlike previous works on FDR's first days in office, Alter is not so much concerned with the legislation that passes during the opening period of FDR's White House years, as pointing out three imperatives: 1) FDR was groomed for greatness and grew into it; 2) how FDR avoided assuming dictatorial powers while the idea was in he air (later ignored by historians); and 3) FDR's extraordinary bond with the American People.

In the 1932 election, the American people repudiated President Hoover as much as elected a new president in FDR. Certainly their existed no bond between the electorate and FDR. However, that changed with the near assassination of FDR that took the life of Mayor Anton Cermak of Chicago. FDR solidified this new bond with action. According to Alter, it really didn't matter so much that FDR's solutions to the Depression worked or not, but rather his demand for action that invigorated the American public.

It wasn't until March 4, 1933 that Roosevelt was inaugurated and by that time the American banking system was near total collapse. President Hoover asked FDR to join him in a joint action to save the banking system, but FDR refused. To FDR that was tantamount to accepting accountability without the requisite authority, plus FDR felt that if things got worse as a result of this joint action, he would inherit the blame. Meanwhile, Democrats in Congress blocked Hoover's attempts to pass laws to alleviate some of the problems facing the country. Alter notes the the 20th Amendment to the Constitution shortened the time between the presidential election and inauguration by six weeks, but it did not impact FDR until the 1936 election. Alter correctly charges that other democracies quickly change governments after an election and that it is dangerous for the United States to allow a lame duck president to stay in office 12 weeks after an election.

Alter claims the "Hundred Days" is an albatross that FDR bequeathed to succeeding presidents. It does offer a measuring stick that can be held up to each president, one that often finds them lacking.

No other politician in 1933 had the required inspirational qualities of FDR. Another president lacking Roosevelt's first-class temperament as well as his charm and guile might have been seduced by the calls for dictatorship. Americans today forget how the Mussolini dictatorship in Italy was admired by Americans in the 1930's for its efficiency. More likely, another president, lacking FDR's ability to inspire, might have left the country equally mired in the Depression, but without hope, leaving the door open for a demagogue like Huey Long to rise to power. The Defining Moment demonstrates how lucky America was to have just the right man at just the right time.