His studied development of a young and vulnerable man who buys into the neo-Nazi doctrine, becomes one of its most committed devotees, gradually learns that the doctrine is a lie, tries to break from it while stopping his brother from repeating his mistakes, is perfect. His characterization is totally believable and frighteningly real. Edward Furlong's Danny shows enough shadings for us to believe that he is capable of becoming a mirror image of Derek. Novice director Tony Kaye has publicly expressed his displeasure at the way his film has been edited, going so far as requesting his directorial credits be removed. While the movie does show us its flaws, it remains a remarkable achievement for a first time director.
Hatred is a losing proposition.
Hatred is not a born or inherited trait. It is a learned behavior. It is an attitude, emotion, or mindset that has to be first placed in the mind. Which means that conversely, it can be removed. It can be unlearned.