Marvel is treading some really interesting ground lately. While the comics are simultaneously being bashed for not being diverse enough and celebrated for changing genders, identities, and races of prominent characters, the movies are quietly slipping in some rather Libertarian-esque ideals, especially in the Captain America films. While the first one was predictably a super-hero war film, the second one was an insightful exploration of governmental surveillance, with SHIELD's Insight helicarriers capable of surveilling and potentially "removing" targets that could question the agenda of the people running them. Similarly, Captain America: Civil War deals with the subject of governmental oversight and Captain Rogers is now two for two in resisting government overreach (violently when necessary), and doing so in a way that presents the topic in a much more effective way than the comics that inspired it did.
Interestingly, there's been an argument that Cap is a soldier, and is clearly in the wrong for disobeying orders. Now I'm no soldier, but I grew up in a military family, but all the same I'll let a soldier debunk that one.
In the comics, there was a tragedy in Stamford, CT that involved a showboating young superhero team, a dangerous villain, and the loss of over six hundred lives which led to a superhuman registration act. In the movie, trainee superhero Wanda Maximoff, recruited at the end of the last Avengers film, is responsible for the accident when she saves Captain America's life by diverting an explosion (that could have killed dozens of people at ground level) not quite far enough into the air to keep it from killing the dozens of people in the building above the market. These events lead to the Sokovia Accords, an attempt to reign in the Avengers under governmental oversight, and both Cap and Tony Stark's team make good arguments for and against it, even having moments where they question their respective decisions. The difference here being that the Superhuman Registration Act of the comics is a clear human rights violation, applying equally to people who operation with self-created enhancements and people born with said enhancements, such as mutants. The Sokovia Accords is much more of a grey area politically, lending Team Stark a much stronger stance.
Marvel films have a formula at this point. They're 12 movies in since Iron Man kicked it off, and they all have similar characteristics: slick character designs that are realistic but pay heavy tribute to their sources, snappy dialogue, and character development that takes place both on and off the battlefield. It's a tribute to the people making the decisions here that, twelve movies in, it doesn't yet feel stale, and there are scenes in this movie that still register a strong emotional response: the fear at Rhodey's "dead stick" moment, Ant-Man's "something big", RDJ's stunning line delivery of "so was I" or meeting Spider-man and Black Panther.
Civil War is both everything we could have hoped for in a super-hero movie, and a fitting chapter in the MCU's story. The only real criticism I have is that this is yet another Marvel film with a weak villain, as has been the norm. (Loki still remains the only well-fleshed out villain in the MCU.) That said, the villain has a good motivation and a brilliant scheme, but we spend so little time with him that he may as well not even be there.
All in all, Civil War is an excellent movie. Well worth the price of admission, even if you want to see it in IMAX or 3D. It's fun, it's compelling, and it sets up the next chapters in the MCU well.