"A Private Little War" leaves an aftertaste unlike all other TOS. It doesn't look like most other episodes either, with a good part of the program set in bright luscious outdoors. But there's no happy ending here, no quick fix with light-hearted laughter on the bridge, and all that remains is a horrible spectacle of a lost, broken Eden. Like Spock under Pike the young Lt. Kirk forged his command philosophy on early planetary surveys, including the no-contact recommendation the Klingons violated in actions the Prime Directive does not recognize. Kirk deals with losing not one but two friends (and loses his cool twice as well), but it's important to remember he doesn't start the civil war. He seeks to end it, by preserving both native cultures.

Michael Witney as Tyree faces the tragic, life-changing moment as leader of his people and friendship with "James." It's not the death of his people that persuades him, it's the combination of his friend's voice and the shocking death of his estranged wife. Nancy Kovack as Nona leaves an unforgettable impression as actress and character. She makes a proper plea for self-defense of the hill people ("Is dying better?") but errs by seeking escalation against the villagers, then commits her final fatal error of betrayal to acquire Kirk's "small box" to bribe Apella. The healing scene of the mugato bite with the mako root is entirely carried by her sensual strength. The Enterprise crew also excels, particularly McCoy, from performing emergency surgery on Spock to an outspoken defense of pacifism to Kirk. Chapel enjoys one of her more memorable appearances, and Dr. M'Benga is prominently featured at his best in the series.

Standing as a disturbing metaphor for the struggle Neural in which finds itself, Spock needs pain to fight back to health and consciousness. But it's never clear why the Klingons sought to mess with the planet in the first place. Because Kirk visited? They need medicines for the sick? Whatever the reason, Kirk tries to convinces McCoy that "war isn't a good life, but it's life" though that does not ease the regret that accompanies his decision. McCoy knows the alternative to retaliation is extinction but can't bring himself to admit it. Kirk stretches the ambit of his orders with a command decision to implement his "balance of power" without consulting Starfleet. He accepts the problems of his friend as his own, introducing yet another burr under the saddle of long-running relations with the Klingons. Not a happy ending at all.