In the battle of Okinawa Ira killed all the civilians & Ira was removed for the battle fatique.
Throughout his time in Okinawa, Ira was a keen and upstanding Marine, though his actions in the atrocity reduced Ira to a broken shell of his former self. Fontaine diagnosed Ira as a paranoid schizophrenic with anti-social psychopathic tendencies. Ira's memories of the war haunted his sleeping and waking moments, unable to tell if he was still fighting in the war. As a result, he was unable to readjust to civilian life and was a constant danger to himself and to others.
Despite his overwhelming insanity, Ira also wanted to alleviate his pain and atone for his mistakes. It is likely that Ira developed his obsession with origami cranes due to the legend that making 1,000 grants a free wish, thus giving him a chance at redemption. He also hoped to secure a samurai sword, and bring it back with him after the Okinawa campaign. However, after being used by Fontaine, Ira could not let go of his Marine mentality. Haunted by death and sadness, Ira sought comfort in the idea that there is a better existence beyond death hence proclaimed to "fight for God", allowing him to fight and kill without guilt. Ira becomes a reluctant villain driven by his insanity. Though arguably, Ira achieved some amount of peace and redemption from helping Elsa, despite his tragic end.