General George S. Patton to 3rd Army, before D Day...
"Some of you men are wondering whether or not you'll chicken out under fire. Don't worry about it. I can assure you that you'll all do your duty. War is a bloody business, a killing business. The Nazis are the enemy. Wade into them, spill their blood or they will spill yours. Shoot them in the guts. Rip open their belly. When shells are hitting all around you and you wipe the dirt from your face and you realize that it's not dirt, it's the blood and gut of what was once your best friend, you'll know what to do. "
EDIT: real words of George S Patton to 3rd Army, repeated by George C. Scott in "Patton."