The Oval Office was burning. On Christmas Eve 1929, not quite two months after the stock market crashed, dessert was being served to President Herbert Hoover and his holiday guests in the State Dining Room when word came that the West Wing was in flames. According to published reports, the president, dressed in black-tie, excused himself to inspect the fire. “At times it seemed as if the flames were subdued,” The New York Times reported, “but there were occasional bursts of blaze through the roof, and the firemen had great difficulty in getting control of the situation.” In the main part of the mansion, the first lady tried to distract the guests by asking the Marine Band to play on.

Metaphors don’t come much more apropos: the Hoover White House, in the wake of the crash, subject to the destructive whims of an uncontrollable force. “Those parts which had not been actually destroyed,” The Times noted of the West Wing, “were gutted and water-soaked.”

America was not far behind. By 1932, the Great Depression had consumed the United States, creating public anxiety and eroding trust in the most basic of institutions. In his landmark trilogy on Roosevelt and the New Deal, published between 1956 and 1960, the historian Arthur Schlesinger Jr. referred to the 1920s and early ’30s as “The Crisis of the Old Order.” America seemed on the cusp of a violent break from the ancien regime of democratic capitalism to . . . well, to what, precisely, was the existential issue of the hour. Would the nation save itself or go the way of Germany and of Italy, seeking comfort in totalitarianism? Or might it choose the path of the Soviet Union, casting its lot with Communism? 

The questions were not academic. Beyond the bankers and the intellectuals, one in four American men were out of work; mobs of hungry youths were loose in the countryside; armed standoffs were already roiling seemingly placid places such as Sioux City, Iowa. A Senate committee was told hard truths: “There are many signs that if the lawfully constituted leadership does not soon substitute action for words, a new leadership, perhaps unlawfully constituted, will arise and act.”

Hoover’s successor knew all this. In the summer of 1932, Gov. Franklin D. Roosevelt of New York had told an adviser that the two most dangerous men in America were Huey Long of Louisiana and Douglas MacArthur, the Army chief of staff: Long could conceivably lead a national coup from the populist left, and MacArthur might manage the same feat from the right. The loudest cheers during Roosevelt’s Inaugural Address on March 4, 1933, did not come from his assurance that the only thing Americans had to fear was fear itself; no, as Eleanor Roosevelt noted, the greatest ovation greeted the new president’s assertion that the present emergency might require him to assume extended wartime executive powers. ...