Sgt. John Basilone

John Basilone is a Marine machine-gun sergeant, already a career soldier when war reaches the Pacific. Steady, plainspoken, and older than most of the boys under him, he leads a gun section with the calm of a man who has done this drilling a hundred times and trusts it will hold when the fighting starts.

Jon Seda plays him without swagger, which is the trick — Basilone's authority comes from competence, not charisma, and the performance lets his men's confidence in him do the talking. The show trusts a quiet, professional soldier to carry weight that louder characters usually claim, and Seda earns it.