After showing the Shakespeare-quoting General Chang who's boss, the crew of Enterprise rushes down to Camp Khitomer to stop the assassination attempt on the Federation President. They accomplish their task quite easily, as it turns out.

What can we say? These folks are pros.

Afterward, Kirk gives a speech, because of course he does. Here's the gist:

KIRK: Some people think the future means the end of history. Well, we haven't run out of history just yet.

The truly important part comes afterward, though:

AZETBUR: You've restored my father's faith.

KIRK: And you've restored my son's.

This is a biggie on two levels. On the obvious level, this exchange significant because it means that the tenuous peace between the Federation and the Klingon Empire will have a shot to grow. Talk about snatching victory from the jaws of defeat.

On a more personal level, however, it shows that Kirk is letting go of his hatred of the Klingons. He and Azetbur are not bonding with each other in spite of the death of their loved ones at the other side's hands—they're bonding because of it. Despite the tenacity with which they once fought against one another, they now see each other as individuals deserving of respect.

The other big aspect of the ending is that this is the original crew's final mission aboard Enterprise. We've seem Kirk and Spock worry about aging throughout the film, and here they're forced to reckon with the fact that their time on Enterprise is up. After everything they've been through, however, the two men are finally ready to pass on the baton to the next generation of leadership.

No, really, we mean it when we say the Next Generation…

Sorry.

That is, these guys will pass on the baton after they take one last interstellar joyride in Enterprise. Hey, they might be a day away from retirement, but that doesn't mean they have to act like it. Kirk's gonna Kirk.