Understanding the signficant difference between these two concepts of narrative.
The currently accepted definition of the Protagonist as being the character the audience empathizes most with is inaccurate. Those who hold onto it are robbing themselves of the opportunity to create unique stories that defy convention.
As stated in my linked item concerning The Confusion Between Main Character and Protagonist, the idea that these two concepts are one and the same is an outdated notion from yesteryear. While there are several films and stories where the two are masterfully combined, there is a relatively unexplored and misunderstood area that seeks to create unique meaning by separating the two.
To Kill A Mockingbird, The Terminator, The Counterfeiters (Die Falscher), The Shawshank Redemption, and The Lives of Others (Des Leben der Anderen) are just a few of the many wonderful stories that have Main Characters who do not drive the story forward. In this article, we'll be taking a look at that last two and hopefully clarify the structure beneath the sheen.
Before determining the Protagonist of the story, it helps to first define what the Story Goal is. The Story Goal is something everyone in the story is concerned with. The successful achievement of this goal will resolve the story's central problem. This problem is presented early on in a story and disrupts the natural balance of things.
In The Shawshank Redemption, problems in the story exist because an innocent man has been unjustly incarcerated. Without Andy's innocence there is no problem and thus, no story. This problem affects everyone -- from the warden to the hardest screw to the inmates and so on. Once Andy is freed, the problems in the story will be resolved and the story will be over. This is the Goal of the story -- freeing an innocent man.
In The Lives of Others, problems in the story exist because a jealous state official wants dirt, real or imagined, on a potentially subversive writer. This problem affects everyone -- from the writer himself, to his girlfriend, to his neighbor and to the Secret Police captain assigned to his case. If the truth about this writer remains a mystery, then the story will be resolved and the story will be over.
The Protagonist is defined as the character pursuing the Story Goal. In Shawshank, this responsibility lies in Andy. Though we don't know it until much later, he spends a lot of his time digging a giant hole and preparing everything for his eventual escape.
The Antagonist is defined as the character preventing the Story Goal. Warden Norton (Bob Gunton) fulfills this role. He's the one preventing Andy from escaping and gives him plenty of opportunities to rethink his escape plans (throwing him in the hole, shooting Tommy, etc.). This is another property of the Antagonist, his or her drive to get others to Reconsider their actions (For more on the characteristics of Archetypal Characters like this, please read my article Character Motivation Defined).
In The Lives of Others, the Protagonist is the writer Georg Dreyman (codenamed "Lazlo" for you Casablanca fans!) and the Antagonist is the jealous state official, Minister Hempf. Georg is constantly pursuing a course of action wherein his blacklisted friends (director Albert Jerska) can have an opportunity to make their art. Hempf does everything in his power to prevent him, including stealing away his girlfriend, Christa-Maria Sieland.
But in both these films we don't experience the events that happen through the eyes of their respected Protagonists. The Main Character is defined as the character through whose eyes we experience the story. We never get to feel what it is like to be in that hole for a month with Andy. We see him go in. And we see him come out. When he plays the music over the loudspeaker, we're not in there with him, we're experiencing it from outside. It's Andy's impact we are feeling (which leads to his other dramatic function as the Obstacle Character, explained in this article The Second Most Important Character in a Film).
Instead, it is through Red's eyes that we witness the events of the story. While he does supply the dramatic function of Narrator, there are deep thematic issues going on within Red that we are personally privy too as well. We are emotionally invested in his journey, due in no small part to the particular shot selections made by Darabont and his crew. In fact, whenever Red makes that long walk to his parole hearings, we the audience assume his position. Those P.O.V. shots are a clear indicator that the filmmakers themselves considered this character the one the audience should empathize with the most.
The same could be said for The Lives of Others and the Main Character of that film, Hauptmann Gerd Wiesler (brilliantly portrayed by Ulrich Mühe). We are emotionally invested in him because again, we are privy to things about him that many others in the story don't know (his pathetic and secluded home life, the hidden looks on his face as he listens in to the conversations below, etc.). The emotional meaning of the story is wrapped around whether or not people like him (the Stasi) can change.
And the emotional meaning behind The Shawshank Redemption is also wrapped around whether or not Red can change. He is more than just the one telling the story. Through him we get to feel what it is like to have become "institutionalized" and a person who has lost all hope. Likewise, in The Lives of Others we get to feel what is like to be someone struggling with the negative labels people ascribe to us. As a member of the Secret Police, Wiesler knows many consider him a "bad man." The emotional meaning of the story lies in whether or not he can resolve these personal issues.
This is why it is important to separate out the concepts of Protagonist and Main Character. When stories are broken or feel incomplete, the reason is usually because the argument being made by the author is inconsistent or illogical. Blending the logical driver of the story (the Protagonist) with the emotional driver (the Main Character) can lead to this confusion. Sure, they can be combined as they have been in many great stories (Up In The Air, The Wrestler, The Silence of the Lambs, Braveheart, The Godfather, and so on), but to require that they must always be one and the same is to discount the subtle and beautifully complex emotional arguments that are being made by films like The Shawshank Redemption and The Lives of Others.
Accuracy should prevail if the art of storytelling is ever to evolve.