Commander in Chief:FDR's Battle with Churchill, 1943by Nigel HamiltonHoughton Mifflin Harcourt, 2016The second volume of Nigel Hamilton's new trilogy about US President Franklin Roosevelt during the Second World was suffers from some of the predictable problems of middle books – and a couple of unpredictable problems as well. The predictable problems are all matters of scale: in the first volume, The Mantle of Command, readers saw Roosevelt assume command of the relatively small and scraggly US armed forces and begin to shape them into something that could answer the unforeseen events of the modern world. And the third volume will contain the high operatic peaks of the story, FDR as head of the most formidable array of fighting forces in the history of the world. But a second volume has the altogether trickier task of presenting the uneven and sometimes unedifying middle period, when Roosevelt was still feeling his way toward confident command but was beginning to understand not only what he wanted but how to get it.Fortunately, Hamilton is such a easy, practiced storytelling hand that he can overcome potential narrative doldrums in his sleep. Commander in Chief is deeply researched and incredibly lively, full of colorful personalities almost always at odds with each other, and it's one of those personality clashes that forms the crux of this volume – and turns up a couple of unpredictable problems, things that are a bit surprising to find in a Nigel Hamilton book. The personality clash is that between FDR and British prime minister Winston Churchill, and the main unexpected element is tact. One of Hamilton's summaries will stand as a good example of the oddly gentle hand he uses when it comes to the disconnect between these two men:

[FDR] had gotten to know Churchill, on the Prime Minister's repeated visits to the White House, probably better than any American during the course of the war. The Prime Minister's moods, swinging from gravity to elation, were part and parcel of his colorful character as a leader. Churchill's approach to modern war was, the President accepted, wonderfully exuberant if often flawed.

The “exuberance” here is something Hamilton frequently characterizes as being the product of Churchill's Victorian and Edwardian upbringing and conditioning, a slightly dotty, slightly boyish kind of enthusiasm about all things military. A less tactful version would present a far more ominous picture of Churchill's drunken blustering and greedy, narrow-minded blundering. But by so consistently resisting the urge to outright indict Churchill, Hamilton's version of his relationship with Roosevelt ultimately succeeds in making the British PM seem all the smaller by comparison. In scene after scene, his strident histrionics are outdone by FDR's aristocratic and increasingly assured manner – and by the fact that by the year of Hamilton's latest chronicle, 1943, the United States was an industrial powerhouse no other country on Earth, much less any of the Allies, could hope to match or do without. As FDR's vision of what he wanted grew clearer, his manner, though usually affable, became increasingly peremptory – and potential confrontations with his nominal partner took on greater and greater signorial tones:

There was one further potion, however, Churchill must take before the two men left Hyde Park, the President made clear.Churchill waited to hear it.The supreme commander of Overlord must be an American, since the largest contingent in the cross-Channel invasion would ultimately be from the United States. This decision, too, the Prime Minister would have to convey to General Brooke.Churchill was shocked – the President's insistence an understandable blow to his patriotic British pride.In the circumstances, though, there was nothing he could say, other than: Yes, Mr. President.

The phenomenon of a civilian commander-in-chief growing into a role of autocratic benevolence clearly fires Hamilton's imagination. As well it should: not since Lincoln had an American president exercised such direct and unremitting control over the country's armed forces, and the central contention of Hamilton's book-series, that Roosevelt was hardly an out-of-his-depth figurehead surrounded by some of the most capable and strong-willed military adjutants in American history, grows stronger with every chapter. Hamilton presents a series of very similar encounters, all with similar conclusions; a crusty old military fixture like George Marshall, the Army chief of staff, is summoned to an audience, told the playbook and the time of day, and sent on their way:

The President had spoken. He was US commander in chief, and it was for Marshall, a US Army chief of staff, to ensure the President's conception be carried out, not keep harping on “critical” insufficiencies, or jeopardy. Period.

By the final pages of Commander in Chief, FDR has achieved a clear but somewhat tenuous ascension over both his own power structure and his histrionic main ally. He's poised for his greatest victories – and for the death that would claim him before he could see the full fruits of those victories. The combination of monumental historical import and monumental potential for histrionics should make that third volume quintessential Nigel Hamilton.