While it might seem strange to put him ahead of people like the morally ambiguous Captain Sisko, who wears his trauma on his sleeve, Kirk has lived through some seriously depressing situations. To explore this trauma and how it makes him a great captain, it’s easiest to look at an episode “Requiem for Methuselah,” and the centuries old immortal human known as Flint. He was born on Earth in 3834 BC with a rare instant tissue regeneration mutation, the result of which led to his extraordinarily long life and an inability to die. He spent most of these years on Earth, starting in Mesopotamia. Over the years he assumed different personalities, including but not limited to Lazarus, DaVinci, and Mozart. He amassed incredible knowledge and intelligence over these years, as well as serious wealth. However, he suffered greatly due to the one thing he missed: companionship.

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Despite being very different, Kirk and Flint has this in common. Kirk, too, was no stranger to loneliness and the despair found within it. He has chosen a path, one that takes him through the stars to amazing worlds where he can do a lot of good, but it never allows for permanent companionship. The closest he got was with Carole Marcus, a love interest at one point and mother to their son. However, their relationship was doomed to fail. Neither of them was willing to compromise their way of life, and the Enterprise is not a good place to raise a child. Kirk’s devotion to Starfleet stopped him from forming meaningful relationships with his lover and son. The Enterprise was a home of sorts, but incredibly lonely.

The parallels between Kirk and Flint are explored during the aforementioned episode. Flint is desperate to find a romantic partner who is not only his equal in intellect and interests, but also immortal like him, so he would never have to be alone again. His solution to this was to create such a being, naming her Rayna, an android with the ability to eventually evolve into a living, breathing human being. The only issue was that the only way Flint could do this was in a fairly convoluted way. The evolution from machine to human could only happen once each of her programmed emotions were fully engaged. Unable to do this by himself, Flint thus finds the perfect catalyst in Kirk.

Kirk and his crew find themselves suffering from a deadly fever, so they set down on a seemingly barren planet to gather a rare element that acts as the perfect antidote. This is where he encounters Flint — who, after some gentle treats to leave, eventually invites them to his home, where Kirk meets Rayna for the first time. As the episode progresses, they fall in love with one another. Rayna truly sees Kirk for the flawed and lonely man he is. In a moment of quiet between the two, she tells him that loneliness is: ‘a thirst. A flower dying in the desert.’ Their romance builds and leads to a moment of jealousy between Flint and Kirk in which the two fight over her. As Rayna witnesses this, all the emotions flood her system. She has to choose between the two, watching them nearly kill one another all for her. She feels love, fear, guilt, anger, all fairly new emotions in huge quantities. It’s all too much for her, and she collapses and dies.

The episode itself was fairly insignificant in the grand scheme of the franchise, with a fairly clunky plot and a sprinkling of sexist objectification. However, the reflection scene at the end where Kirk looks back at the events of the day is fantastic. Talking to Spock, who is no stranger to failures himself, Kirk talks about how he and Flint were both just lonely men, and their loneliness made them act in terrible ways. The whole ordeal has been a lot for the captain, falling deeply in love with someone, only to see them die in his arms due to his own actions. The episode reveals Kirk’s greatest adversary. It’s not Khan or Flint, but his own loneliness, something he battles constantly. The trauma he faces over the years, the death of Rayna, and his inability to see and take care of his son are just small snippets of his traumatic life. Everyone he seems to care about leaves him.

Despite this, Kirk chooses to carry this pain, believing it is what makes him a great leader. When he encounters Sybok, Spock’s half-brother, the Vulcan offers to take away all his pain, releasing him of all his trauma. Yet, Kirk declines and tells him that he needs it all. He keeps it together very well, seemingly a paragon for his crew, but under it all he is deeply flawed. Without it, who knows what Kirk would emerge, no longer having to overcome it every day and try his best to simply maintain composure. The episode shows all this, laying bare all the pain that has simmered beneath the surface. It finally offers some insight into how Kirk managed to become one of the best Starfleet captains the Federation has ever seen.

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