Saga of how FDR worked the shortsighted Churchill on war strategy

It is a commonplace that World War II was a two-front war. But only now, nearly three-quarters of a century after the war ended, do we fully realize that America’s president was fighting a two-front conflict of his own — one against the Axis powers and one against Winston Churchill, one requiring remarkable organizational skills and the other all of the 32nd president’s political powers and personal diplomacy.

The struggle between the pair — portrayed in Churchill’s memoirs as the closest of allies — produced what Nigel Hamilton describes as “one of the most contentious strategic debates in the history of warfare,’’ adding, “it is not too bold to say that upon its outcome rested the outcome of World War II, and thus the future of humanity.’’

The year 1943, the focus of Hamilton’s “Commander in Chief,’’ was the staging ground for the supreme test of trust between the English-speaking leaders, one that revealed Churchill as “a Victorian not only in his colonial-imperialist mindset, as President Roosevelt often remarked, but in his understanding of modern war.’’ Hamilton’s book is the second volume in his biography of FDR as a war president, following his “Mantle of Command’’ (2014). The project is thus the rebuttal to the Churchill multivolume history of the war that, through its Book of the Month Club edition, sits on the shelves of thousands of homes, mostly unread but still holding sway over the great narrative of the great generation.

In this latest book, Churchill — characterized by FDR as his “active and ardent lieutenant’’ — emerges neither as visionary (a popular misconception, Hamilton would argue) nor as villain in the crafting of Allied battle plans, but mostly as obstinate. He understood, better than most and perhaps more clearly than Roosevelt, the threat posed by the expansionist impulse of the Allies’ Soviet partner, but he did not understand the broad contour of the military struggle and was preoccupied with the Mediterranean and continually underestimated the power and skill of the Wehrmacht. Indeed Hamilton, a senior fellow at the McCormack Graduate School at University of Massachusetts, Boston, contends that had Churchill prevailed in the dispute over whether to mount a cross-channel invasion of Europe — he was adamant in his skepticism — the Allies may well have lost the war.

It was in this period that Roosevelt began to shape his ideas of what became the post-war United Nations, different in structure and intent from the League of Nations that had failed to win Senate approval and that had broken the heart of his Democratic predecessor and onetime boss, Woodrow Wilson. FDR was not going to repeat Wilson’s error of leaving the post-war world to the post-war period.

The wonder of it is that after all these years and all the thousands of books written on the subject, the war still retains the power to shock and surprise. Here is one of Hamilton’s shocks and one of his surprises: General George C. Marshall favored a 1943 invasion of France over one of Sardinia because, he argued, the former would cost only men’s lives but the latter would imperil ships, which be believed would be harder to replace than troops. And the Germans knew that FDR was to meet Churchill at Casablanca, but they thought the venue was Casa Blanca, or the White House.

One of the principal themes is Hamilton’s contention that Churchill was a deeply flawed military strategist, the result of what he called “the irreconcilable difference between his grand strategic ideas and his too-often- ill-considered opportunism — a difference affecting tens of thousands of soldiers’ lives.’’ He portrays Churchill as a prisoner of his reliance on air power and small offenses at the periphery of Germany’s new European empire.

FDR, too, saw the flaws in the man he nonetheless considered an historic figure. He vigorously opposed Churchill’s determination to retain Britain’s colonies, describing his wartime partner as “a great man for the status quo.’’ Of Charles DeGaulle, scourge of a parade of American presidents, he said: “I can’t imagine a man I would distrust more.’’

Roosevelt had a broad historical view of the origins of World War II that would have troubled both Churchill and DeGaulle. “Don’t think for a moment, Elliott, that Americans would be dying in the Pacific tonight, if it hadn’t been for the shortsighted greed of the French and the British and the Dutch,’’ he told his son. “Shall we allow them to do it all, all over again?’’

In the end, Roosevelt coaxed the British rather than cajoled them, and persuaded rather than pummeled Churchill. He sent the British military leaders on a Williamsburg holiday and bid Churchill to accompany him to Shangri La, now known as Camp David. The tactic of what Hamilton called “extreme hospitality’’ worked extremely well with British military officials. The prime minister would take more time. But the president would prevail and so, in time, would the Allies.

COMMANDER IN CHIEF:

FDR’s Battle with Churchill, 1943

By Nigel Hamilton

Houghton Mifflin Harcourt, 464 pp., illustrated, $30