CHAPTER ONE The Invisible Wall My men were in battle dress for the landing—steel helmets painted green, dirty green jackets, pants, cartridge belts, heavy field shoes. The Caribbean was so deep blue it hurt the eyes. You could look straight down into it until it made you dizzy. Sharks, some of them monsters, congregated from all directions. Marines waiting to debark shouted derisively at the sharks; but it was noticeable that they didn't pull any funny business on the slings, and they didn't let