Earlier this year, the Marvel Cinematic Universe heroes fractured in Captain America: Civil War due to the passing of the Sokovia Accords. Differences in opinion over Bucky Barnes' innocence made matters worse, and although the movie's conflict wrapped up, the two sides are still at odds with one another. We already know that Earth's Mightiest Heroes will have to reunite in 2018 for Avengers: Infinity War, but it sounds like one of the MCU newcomers, Doctor Strange, will serve as an excellent mediator for them.
I think [Doctor Strange] has to be Team Doctor Strange. His job title is defender of the fabric of reality. I mean, he fights other dimensional threats that are beyond the perceptions of that very potent squabble [between Cap and Iron Man], and I'd like to think he's going to help them both, rather than take sides.
Director Scott Derrickson concurred with Benedict Cumberbatch's statement, adding that the Master of the Mystic Arts is on his "own team" due to his position as "gatekeeper between our world and other dimensions." Although Stephen Strange was mentioned as a potential threat to HYDRA in Captain America: The Winter Soldier, Doctor Strange marks the former surgeon taking his first step into a larger world, to borrow a Star Wars line. However, unlike the other superheroes, he's the only one who stands in the way of evildoers and other forces from alternate dimensions that attack Earth. He can't be bothered with the "squabble" between Team Iron Man and Team Captain America.
It's unclear when exactly Doctor Strange takes place in the MCU, although a shot from one off the trailers indicates it may be around the Avengers: Age of Ultron period. Regardless, since Stephen Strange's attention is devoted to keeping an eye on supernatural forces, he's not concerned with the changing dynamic between the other superheroes. He doesn't have a stake in either the Civil War or the Sokovia Accords. In fact, the only thing he arguably has in common with the Avengers is that he wants to keep Earth safe from those who would do it harm. That's exactly what Strange will do with them in Infinity War, and hopefully while he's with Earth's Mightiest Heroes, he can help mend some of the wounds incurred during the third Captain America movie. In a sense, he'll be acting as a doctor in a different way.
Doctor Strange hits theaters in the U.S. on November 4, and following that, the Sorcerer Supreme will participate in the superhero-packed insanity that is Avengers: Infinity War on May 4, 2018.