Stalemate on the Western Front would drain its military strength, blockade would break its economy, and propaganda leaflets such as Hitler and the Working Man would undermine the morale of its people. Publicly, Chamberlain was predicting a three-year war; privately he expected starvation, public discontent, and raw material shortages to force Hitler—or hopefully, a new German leader—to the negotiating table much sooner. In early November 1939, he told Joe Kennedy, the US ambassador, “I don’t believe [the war] will go beyond spring.”

In the autumn of 1939, Americans could be forgiven for thinking that Chamberlain did nothing without first consulting Kennedy. “You and Hitler are running neck and neck to see who has his picture more often in the New York papers,” a friend wrote the ambassador from America. “It is ‘Kennedy goes to Downing Street,’ ‘Kennedy sees Halifax,’ ‘Kennedy has his shoes shined’ . . . the implication in the New York newspapers is that Chamberlain does not dare to go to the lavatory without you.” Even more than making money, Joe Kennedy’s special gift was self-promotion. In 1939, there was scarcely a literate American unfamiliar with at least one part of his biography, whether it be his years in Hollywood; his Wall Street career; his chairmanship of the Securities and Exchange Commission; his large, photogenic family; or his 1938 appointment as American ambassador to Britain. Even readers unfamiliar with the details of his life recognized Kennedy’s big, toothy Irish grin from a dozen magazine covers. Two weeks after the German invasion of Poland, Time hailed the ambassador as the war’s “indispensable man.” “With 9,000 Americans to shepherd in England, with tangible U.S. business interest under his command, with British bigwigs to see, Franklin Roosevelt to keep informed, Joe Kennedy has a bigger job.”

Time had it backward. Kennedy’s “bigger job” was essentially that of a concierge. In the early weeks of the war, while the White House and State Department debated the US response to the European crisis, Kennedy was booking passage for Americans anxious to flee Britain. In early October, when a British colleague mentioned that Roosevelt and Churchill had initiated a private correspondence, the ambassador, who had not been informed of the correspondence, had to hide his surprise. In Washington, Kennedy’s stock began to fall in 1938 when he suggested that the democracies and the dictatorships should “bend their energies toward . . . solving common problems and attempt to establish good relations” in a Trafalgar Day speech. In Downing Street and in certain precincts of Whitehall, however, he remained a welcome presence. In August 1939 he encouraged Rab Butler, the undersecretary of state for foreign affairs, who needed little encouragement, to offer Hitler a proposal “he could hang his hat on,” and in early September he urged Chamberlain to “put in some war regulation that would make the British public think twice about going to war.”

After the Soviet Union occupied eastern Poland on September 17, Kennedy’s appeasement turned into defeatism. From the autumn of 1939 through the summer of 1940, he sent Washington a stream of cables questioning British resolve. “They [the British] have no intention of fighting,” he wrote in one. King George VI, who had been made aware of the cables, complained publicly about Kennedy’s defeatism, and the Foreign Office found the ambassador’s attitude worrisome enough to open an investigation. Was Kennedy a defeatist because of his association with the pro-German aviator Charles Lindbergh? Because he was politically ambitious and “did not want to be tarred with the pro-British brush”? Or because he was an Irish American and thus “predisposed to tweak the lion’s tail”? Oddly, the Foreign Office overlooked the most obvious explanation: Kennedy was an American.

By mid-September 1939, it was becoming difficult to traverse a road or a byway in America without encountering a “Keep the US out of War” sign. A month later, a Gallup poll reported that, by a 95 to 5 percent margin, Americans favored neutrality. Even Abraham Lincoln did not poll that high. “The country is literally drunk with pacifism,” a French journalist wrote from New York. The reasons for the antiwar feeling were many, starting with the nearly universal American belief that, in the Great War, Britain and France had outplayed the United States. For its 116,708 dead, the US had gotten roughly $10 billion in still unpaid European debt and precious little else. Beyond that, every American had his or her own personal reasons for supporting isolationism: German and Irish Americans because of a historic enmity toward Britain; midwestern isolationists from the conviction that the only country an American should defend was his own; businessmen because a world war would disrupt the international economy; and the parents of draft-age sons, such as Ambassador Kennedy, for fear that American boys would be dragged back into the European abattoir.

In the late 1930s, Congress responded to isolationist sentiment by passing the Neutrality Acts, which forbade the sale of US arms and other war materials to belligerent countries. Under pressure from President Roosevelt in early November 1939, the acts were amended to allow belligerents to purchase war materials in the United States. The cash-and-carry provision, abrogated in 1937, was also reinstated. This allowed other nations to make purchases in the United States, provided they paid immediately and shipped their purchases on non-American ships.