Colonel Sherman T. Potter

Potter arrives at the 4077th as the new commanding officer, a career Army man and career surgeon in equal measure, replacing chaos with calm competence. He's older, plainspoken, fond of his horse and his bourbon, and unimpressed by nonsense—but he listens before he judges, and he runs the unit like a father who's also a good doctor.

Harry Morgan gives Potter a gruff warmth that never curdles into sentimentality; he's stern without being humorless, principled without being rigid. The writing trusts him to hold the ensemble together after a cast overhaul, and Morgan repays that trust by making authority look like decency rather than rank—so his rare outbursts of anger actually land.