There were some solid messages here and there about family and post war mentality, but not good enough to cover the flaws in this movie.
Besides that, Brothers is a masterful Cain and Abel story of, well, two brothers. One is happily married with children and one is a low-life. After a traumatic event, the two brothers switch and turn into each other.
The three leads are absolutely brilliant. Tobey Maguire, in general, really steals the show. Say goodbye to Peter Parker! This guy can do serious drama. Natalie Portman is also amazing.