One big reason you should read my two most recent books:

[Chris Kyle] and his fellow platoon members spray-paint the white skull of the Punisher from Marvel Comics on their vehicles, body armor, weapons and helmets. The motto they paint in a circle around the skull reads: “Despite what your momma told you … violence does solve problems.”
“And we spray-painted it on every building and walls we could,” Kyle wrote in his memoir, “American Sniper.” “We wanted people to know, we’re here and we want to f*** with you. …You see us? We’re the people kicking your ass. Fear us because we will kill you, motherf***.”
The book is even more disturbing than the film. In the film Kyle is a reluctant warrior, one forced to do his duty. In the book he relishes killing and war. He is consumed by hatred of all Iraqis. He is intoxicated by violence. He is credited with 160 confirmed kills, but he notes that to be confirmed a kill had to be witnessed, “so if I shot someone in the stomach and he managed to crawl around where we couldn’t see him before he bled out he didn’t count.”
…He justified his killing with a cloying sentimentality about his family, his Christian faith, his fellow SEALs and his nation. But sentimentality is not love. It is not empathy. It is, at its core, about self-pity and self-adulation. That the film, like the book, swings between cruelty and sentimentality is not accidental.
“Sentimentality, the ostentatious parading of excessive and spurious emotion, is the mark of dishonesty, the inability to feel,” James Baldwin reminded us. “The wet eyes of the sentimentalist betray his aversion to experience, his fear of life, his arid heart; and it is always, therefore, the signal of secret and violent inhumanity, the mask of cruelty.”
“Savage, despicable evil,” Kyle wrote of those he was killing from rooftops and windows. “That’s what we were fighting in Iraq. That’s why a lot of people, myself included, called the enemy ‘savages.’… I only wish I had killed more.” At another point he writes: “I loved killing bad guys. … I loved what I did. I still do … it was fun. I had the time of my life being a SEAL.” He labels Iraqis “fanatics” and writes “they hated us because we weren’t Muslims.” He claims “the fanatics we fought valued nothing but their twisted interpretation of religion.”

– from Chris Hedges’ article about the movie and book American Sniper, which you can read here:
http://www.globalresearch.ca/american-sniper-killing-ragheads-for-jesus/5427723
My two most recent books directly address the toxic cocktail of religion and hostility:
Why Did Jesus, Moses, the Buddha, and Mohammed Cross the Road confronts the twisted theocratic thinking of the book and film’s protagonist, Chris Kyle.
We Make the Road by Walking presents a way of reading the Bible that produces peacemakers, not snipers.