It just occured to me that while the Punisher is not as crazy as Batman, it's more likely his behavior is one who has lost faith in the system. The death of his family is a tragedy that could have driven him over the edge. But Frank has fought for his country and the law for many years. He understands how it works and what it's trying to achieve. So trauma couldn't shake that apart. I think there's a more rational, pragmatic attitude that writers have lost sight of.