Just watching TNG 'homeward', where an entire species must die because of the application of the prime directive. Which got me thinking: in-universe, what are the ultimate reasons behind the prime directive ? I mean, I can understand a reasoning of 'not interfering with a species' natural development before they are ready for it.' I can also accept a reasoning of 'on the whole the prime directive does a lot more good than harm'. But letting an entire species die just because 'interference might prove harmful in the long run' ? I'd say extinction is the greater harm here. So I'd think that there should be some pretty solid motives to still not interfere, but we are given none in this ep. All I get is a weird two-liner between Rozhenko and Troi coming down to the statement that the P.D was ultimately not meant to help people survive but to ensure non-interference -- which still says nothing about the why. So, if the ultimate goal is not to protect primitive cultures, then what is it? Or should I just see this episode as a moronic 'befehl ist befehl' application of the PD, where an exception should have been required ?