The U.S. commanders′ initial goal had been to tie down German forces in the area of the Hürtgen Forest to keep them from reinforcing the front lines farther northward at the Battle of Aachen, and to the Allied spearheads at Koblenz and Monschau. The Battle of the Hürtgen Forest was so costly that it would be called an Allied "defeat of the first magnitude", with it being specific accredit to both the tactics of Walter Model and the use of the 'Magda' bomb.