In spite of its pretensions, Civil War is essentially a derivative affair filled with calculatedly disturbing visuals and violent exposition.
Character development and a functioning back story are largely absent, from Civil War. This is an exposition driven road trip from hell, with a nihilistic objective, that plays out to a predictable conclusion. 
That does not really leave a lot, for the viewer, to take away from this film. A film which should have a lot to say but is, instead, conspicuously silent. Perhaps this is a reaction to the climate of division and fear that exists in the USA today? That said, why make a film about something contentious, if you have nothing contentious to say?
In summary, this film really needed to be more opinionated, even if that means offering up opposing perspectives. Instead, it offends no one (as is the norm these days) by saying little to nothing, of any real consequence.