Patton's ego seems tame compared to that of Gen. Mark Clark, commander of the American Fifth Army in Italy. Atkinson paints Clark as so obsessed with capturing Rome himself that he pondered turning his own guns on the British if he thought they would enter the city ahead of him.

At the heart of "The Day of Battle," though, is the foot soldier, the men pinned down at Anzio, the troops sent relentlessly into fortified German lines. The Italian campaign was the battlefront that most resembled the battles of World War I, armies flinging themselves at each other again and again over the same ground.

Atkinson juxtaposes the fighting for inches with the grave realities of Allied war-making politics and how much blood was spilled because of clashing egos. He also explores many of the war's darkest secrets, from its largest incident of fratricide (Allied gunners in Sicily opening up on their own planes and paratroopers), to the disastrous results when a ship containing a cargo of mustard gas is bombed in an Italian harbor, to the atrocities committed on both sides.

His deeper exploration is whether the war in Italy needed to be fought at all. It was, history proved, of little strategic importance. But it was, Atkinson concludes, necessary for Stalin's appeasement and diverting German resources from the preparation of defenses for the invasion of France.