His shooting the terrorist also ensures that John McClain will reunite with his wife, so his action as an individual also serves to help the story prove its premise. Were this not the case, the patrol cop would be an unnecessary character. What's at stake for one of the terrorists in Die Hard is that he kill John McClain. The action of the story, his confrontation with John McClain, resolves this issue. His defeat, and later death, is one more obstacle overcome along the way to the story premise being proved.
Individual characters can have issues that they resolve within the world of the story.
Individual characters acting to achieve, and achieving, personal goals are what gives a story its continuous pull on a reader's attention. Within the main question of how what's at stake in a story will be resolved might be dozens of individual issues and conflicts that are raised and resolved as a story progresses. However, each of these conflicts is included only because every one of them helps the story move toward its fulfillment. Just as individual characters or groups of characters can feel they have something at stake in meeting personal goals or in the final outcome of the story, a scene in a story can present something to be at stake. In Batman Forever , Bruce Wayne goes to a party where a device created by Enigma is demonstrated.