Sands of Iwo Jima - Allan Dwan

After his wife takes their son and leaves him, Sgt. John Stryker is an embittered man who takes his misery out on the men under his command. They're a bunch of green recruits who have a hard time dealing with Stryker's tough drills and thicker skin. Even his old friends start to wonder if he's gone from being the epitome of a tough Marine Sergeant to a man over the edge.