We made it easy on you for the protagonist, but now you're back on the hook. Who is the real antagonist of this story? We have a couple suspects in mind. First, the Third Reich, i.e. the instrument of violent anti-Semitism that threatens to destroy our protagonist. More specifically, all the people who are part of the Third Reich: Captain Julius Rothe, the Nazi sergeant, and the firing squad. But Jaromir doesn't seem to feel a lot of antagonism toward these human persecutors, does he?
So where do we go from here? Well, we're going to do a little sleuthing. Let's take a look at the story-within-the story. The main character of Jaromir's play, the Baron Römerstadt/Jaroslav Kubin, seems to be a projection of Jaromir himself (see our discussion of this relationship under "Foil"). So figuring out who the antagonists of the play are might give us a hint about who Jaromir's real enemy is, too. (After all, the play is called The Enemies.) Okay, so here we go: the baron feels that he's being persecuted by an untold number of secret enemies, but as it turns out, it's all in his head. The entire situation turns out to be the paranoid imagining of the baron's true persona, Jaroslav Kubin.
We're getting there, be patient with us. We know that the human enemies aren't actually real in Jaromir's play, so what does that say about Jaromir's human enemies? Are the Nazis just doing their jobs? Is their interaction really as impersonal as a game of chess, or the workings of vegetables or planets, as the narrator implies?
If the Nazis aren't the enemies, who or what is? Well, if Jaromir's goal is to complete his play and the only thing keeping him from doing so is time, then maybe we have our answer. Can time be an antagonist? Bottom line: there's no real clear-cut answer here, and we're pretty sure Borges did that on purpose. What do you think?