Foil Characters...fun

After reading Act 1 of Othello, the Moor of Venice by William Shakespeare, it seems pretty clear that Iago and Othello are set up as foil characters.  Othello, the title character and (I think) protagonist of the story, is trustworthy, honest, and an honorable servant of Venice.  On the other hand, Iago is cunning, deceptive, and vengeful.  He says himself "The Moor is of a free and open nature / That thinks men honest that but seem to be so (I.iii.379-80)."  He is admitting that he is not honest and plans to fool Othello.  Meanwhile, Othello calls Iago honest and leaves his wife under his care.  These two characters obviously do not think alike.  My only confusion is as to which one is the protagonist.  My first thought is that Othello is the protagonist.  He is the stereotypical "hero" and the namesake of the play.  However, the play is told mostly from Iago's point of view.  I suppose the later action of the story will determine who the true protagonist is.