Though most will simply remember this as the episode in which the writers kill off Vedek Bareil, there's more to look at. What could have been a maudlin melodrama is instead a sincere story about one man's sacrifice and Bashir's moral dilemma to keep him artificially alive. The reasons, however, behind Bareil's deletion from the recurring character list is a ponderous issue.
When Bareil and Kai Winn make an unannounced shuttle trip to DS9 to finalize a peace treaty with the Cardassians, an accident seriously injures Bareil, who dies on the operating table. Fortunately (i.e., medical technobabble), some residual radiation manages to preserve him long enough for Bashir to perform a miracle and bring him back.
It is not, however, that simple. Bareil has suffered permanent damage due to the radiation, and Bashir wants to put him in indefinite stasis in hope of a cure that could be years down the road. Bareil feels compelled to be sure the negotiations go through as planned, and Winn says she can not finish the talks without him. Bareil demands another option from Bashir, who reluctantly offers an experimental drug as a dangerous alternative. The drug has been known to cause chemical poisoning of the brain and other vital organs, but it may be able to keep Bareil healthy enough—and alive long enough—to finish the negotiations. Bareil presses on, enduring an increasing amount of pain with each succeeding scene, as the drug slowly destroys his body.
It's the classic example of the man willing to die for his cause. The noble Bareil is completely aware that going through with the treatments will likely kill him but accepts it as the price to pay for peace with the Cardassians.
But "Life Support" also works on the level involving Bashir's dilemma. He has to perform these experimental medical procedures at Bareil's request. The drug takes its toll on Bareil, and his major organs begin to break down, forcing Bashir to replace them with artificial implants. This leads him to appeal a plea to Winn, hoping she will take over the talks and allow Bareil to rest with a chance of surviving.
It's the best vehicle this season for Bashir as a doctor; we get to see him in action playing for a single motive—his patient's welfare. The episode sports his first outing doing real operating room surgery. Plenty of effective interaction with Winn and Kira, the interested parties in Bareil's condition, gives the episode ample substance.
He has to break news to Kira that her lover's chances of survival are slim to none. Meanwhile, he has to keep his patience with Winn, who remains adamant that Bareil is the only one who can keep the peace process moving forward, and must continue with the treatments at all costs.
This again brings up the question of Winn's competence as Bajor's leader. In a rather thought-provoking scene, Bashir confronts Winn and tells her what he thinks of her unwillingness to stand alone. He calls her a coward. He believes she uses Bareil as a political shield, someone to take the blame should the talks fail. It's a good point, given Winn's questionable past ("In the Hands of the Prophets"). Even though Winn has been softened into a more sincere character of late, it's nice to know the writers still acknowledge her past and obvious flaws.
Eventually, Bareil suffers permanent brain damage, and Bashir reluctantly replaces part of his brain with positronic implants so the treaty can be finalized. An eerie scene displays a detached Bareil who, with part of his mind replaced with a machine, loses much of his grasp on reality and emotion, speaking in a slow, confused monotone.
The peace treaty is successfully signed, thanks to his assistance, but Bareil is a lost cause—Bashir expects total brain failure within hours. This leads to another interesting speech Bashir makes. When Kira hopes that replacing the rest of his brain may save him, Bashir tells her that he would simply be a machine without a spark of life. "He'd be dead. And I will have killed him." (One could even argue that this is an allegorical anti-euthanasia moment.) Bareil dies, but with some dignity. It almost makes up for the ridiculous moments of his character's appearance in "Fascination."
However, there are a few problems I have with "Life Support." Though it's an important event and I have faith that the writers will utilize it properly in the future, I question how the episode brings about peace with Cardassia completely out of nowhere. I also want to know the writers' impetus behind killing off Bareil in the first place. It makes sense standing alone in this episode, but why in the world would they delete a character so important to this story arc—a very significant if not the central arc of the series—just to fill the requirements of one episode?
I sure hope that Bareil's death isn't simply the writers' way to remove Kira's love interest from the show so she can explore a relationship with Odo. That would be unforgivable. Whether people realize it or not, Bareil meant more and could've continued to mean more to the series than to be Kira's boyfriend.