In the final scene of Star Trek: The Next Generation, "The Vengeance Factor" (episode 9 of season 3), why did Riker
have to kill Yuta?
It is clearly said in previous scenes (by Dr. Beverly Crusher) that a microvirus, embodied in Yuta, was only harmful to members of the clan with which Yuta’s clan was fighting. If so, couldn't he simply use force? Like catch her, and block her from reaching Brull or doing anything less harmful? If he wouldn't have enough force, I think that Worf was somewhere close to help him.
In my opinion, "The Vengeance Factor" is one of the best episodes of Star Trek: The Next Generation. But its final scene is simply terrible. Was it really necessary to end it in such a poor / lame / American-western-like way (where every "evil" must eventually die at the movie’s end)?