A victorious American army, having driven through Belgium almost unopposed, ran head-on into German soldiers on their own home ground, in some of the most rugged country in western Germany-and at the beginning of the worst fall and winter weather in decades. In late 1944, American forces advanced into the hilly, heavily wooded Hurtgen Forest southeast of Aachen, Germany. For weeks, without a clear-cut reason for attacking through the forest, U.S. commanders nevertheless ordered units of as many as seven divisions into the woods to be chewed up by German infantry and artillery. Small units,...