[jonnathanson]

Ok, wow, I stand corrected then. I apologize. For some reason I'd always assumed he was half-human; I don't know where that assumption came from. Maybe it's a bit of mental conflation, given how frequently other aliens-on-the-bridge in Trek series are half human.

Even still, I do think he was choosing between two worlds. Pretty much every time he encountered Klingons in TNG, they made comment about his wearing a Federation uniform and serving under humans. And there were several occasions where the derision went the other way: humans (or non-humans) would chide Picard for having a Klingon officer. Whether we choose to call this trope "stranger in a strange land," "choosing between two worlds," or something else altogether, the fact remains that Worf was an atypical Klingon in atypical circumstances, often forced to choose between whether he was to pursue his Klingon heritage and familial obligations to their fullest, or whether he was to be a Federation/Starfleet officer -- the requirements and laws of which often ran in direct contradiction to Klingon ethics. That was, indeed, a major source of drama for Worf throughout his character's appearance on TNG.

In DS9, yes, you could say he chose to be a Klingon. And by the end of the show, he made that choice unequivocally. Even still, it would have been nice to have had some remnant of the conflict remain. If only because that conflicted forces tradeoffs.