12 Darkest Star Trek: Deep Space Nine Moments
3. Jake Watches A Soldier Die - Nor The Battle To The Strong
Everyone is a badass until bullets actually start flying, and no one better embodies this than Jake Sisko.
When Jake and Bashir go to help out an outpost under Klingon siege, Jake - seeing the horrors of true combat for the first time - runs off in fear, leaving Bashir behind. When he takes a break from fleeing, he finds a soldier slowly dying in the dirt. After talking for a bit, Jake finally reveals what he did to the soldier just as he starts actually dying. The soldier spends his last moments chastising the young Jake, telling him that he can't just write off running away and leaving behind a comrade a mere "mistake", and that life doesn't work like that.
This entire episode is basically about the adorable young Jake Sisko being forced to grow up by the ravages of war, having his every illusion of heroism and glory irreparably shattered before our very eyes. And it's all personified in a single moment, where a soldier spends his last moments on this Earth calling Jake out for being a coward.