The Germans would have won World War I if the U.S. military had not intervened, argues history professor Geoffrey Wawro in Sons of Freedom: The Forgotten American Soldiers Who Defeated Germany in World War I (Basic Books).

He depicts battles and deliberations during the war that the French and British were on the verge of losing in 1918.

"The million or so Americans who fought in World War I haven't received nearly enough credit for their astonishing courage and sacrifice," says Wawro, who also is director of the Military History Center.