This an episode with some fascinating aspects and some genuine liabilities. On the negative side there's the really terrible white ape creature with the ridiculous rhinocerous horn on its head. There's no reason for this creature to have been included (it really belongs in an episode of LOST IN SPACE) when the producers could easily have found some other way for Kirk to have been stricken down - severe allergic reaction, food poisoning, alien insect bite.
The second liability is Kirk's solution - arming the peaceful tribe so that the balance of power is re-established. Surely, a security team could have beamed down in the middle of the night, removed the weapons and destroyed the forge. But of course then there would have been no story. So, sloppy, sloppy storytelling.
On the plus side, that same liability is also one of the episode's strengths. Kirk's answer to the problem. Clearly Kirk is not happy with the solution, but has the strength of character to push his solution onto the situation, despite the protests of Dr McCoy, and the conscience to feel bad about it.
The final plus is the incredibly sexy and ambitious Nora (played by Nancy Kovack). Kovack had been around tv and low budget films for years yet was just 31 when she made this. She certainly made her mark here as one of the great STAR TREK babes.
Well worth a look ...