Check out this interview with Joss Whedon on the Batman v Superman trailer. He drew some interesting parallels between the Batman v Superman story arch and that of the upcoming Avengers: Age of Ultron plot. 

Whedon's main point? Not everyone will agree 100% of the time. In Avenger's you have two groups each fighting for what they think is the right path for the prosperity of Earth. We see the same conflict in Batman v Superman. Two heroes at an impasse because their respective ideas of good do not agree.