"I regret that we meet in this way. You and I are of a kind. In a different reality, I could have called you friend."
When it comes to characterization, Balance of Terror can hold its own against any above-average DS9 episode -- and no, I am not even kidding.
Dad's alternate title for this episode is "First Romulans" -- but lucky for us, the story goes far beyond a mere introduction of one of Trek's major races. More details can be found here courtesy of Memory Alpha.
Why the high praise in the opening comment above? Well, if you've been with us long, you are no doubt aware of my proclivities -- in particular, my love for tragic characters. The character who feels bound by patriotic duty to do things he personally abhors is a character type that gets me every time.
And that brings us to the heart and soul of Balance of Terror: Mark Lenard's Romulan commander. The writer here only has half an episode (or less) to flesh out Kirk's adversary -- and yet he manages to create an astonishingly sympathetic and layered "villain" who carries out the orders of his newly aggressive government with what can only be described as "determined despair." The Romulan commander doesn't want a new war with the human race; he feels heartsick at the prospect. At the same time, he's not going to throw the fight because his own sense of honor won't permit surrender. Further, unlike his war-happy underling, he refuses to indulge in the ethnocentric belief that a Starfleet captain is somehow less cunning. The Romulan commander sees Kirk as an equal and behaves accordingly.
Now does my comparison to DS9 make sense?
This episode, of course, has many additional strengths. As SF Debris and others have highlighted, its overall approach to war is balanced and mature. The script acknowledges that war is often a necessary evil; indeed, it is Spock, the voice of logic and reason, who delivers the argument in favor of retaliating when the Romulans' violations of their century-old treaty are discovered. On the other hand, the impact of war is never white-washed. Between Stiles' lingering bigotry and the wedding (between Martine and Tomlinson) that is cruelly interrupted, war's negative effects are always realistically portrayed. Thus, the episode simultaneously avoids both a naive and simplistic pacifism and the impulse to glorify what should not, in truth, be glorified. As far as I'm concerned, that is no mean feat.
'Tis a damn near flawless script that, in its time, revealed the true potential of the franchise.
Mark Lenard steals the show here, I think. I can understand why they brought him back.
See the discussion above regarding the episode's treatment of war.