The Deadly Brotherhood provides accounts from veterans of nearly every division (armor, infantry, airborne, marine) that saw combat in World War II. Ultimately the most basic question is why they did it. Why did these American combat soldiers endure what should have been unendurable? What made them perform effectively and cohesively and draw on reserves of courage that they probably thought they did not possess? Author John C. McManus discovers that to a great extent, they fought for one another, made real by a bond that is accurately termed a "brotherhood." The GI leaving his foxhole in the Ardennes might not have liked the soldier next to him, but he would do almost anything to help him. The same was true for his counterpart in Italy and the Pacific. The brotherhood was not unique to any one unit, sector, or theater. It was pervasive among the troops who fought the war.