I often see arguments like these that basically go "well if only some extraneous event would have gone slightly differently said person would not have had to resort to this". The propensity to lay blame to pathetically extraneous phenomena, and remove all idea of human agency from analysis is representative of our modern "touchy-feely" idea that if only we'd all love and hug and sing kumbaya, bad stuff wouldn't happen. WRONG. At the end of the day, this guy - of his own will - decided to harm others by the multitudes. They strategically picked a venue with an incredibly large gathering and they CHOSE to commit this horrendous act. Now I'm not saying you're wrong and that the stigma of being a "loser" in immigrant communities may indeed been a factor in leading them to commit such a heinous attack on other human beings. What I'm saying is it's no excuse for it and if that's the case, then every homeless guy, riff-raff, and just anyone who plain isn't satisfied with their lives should feel free to commit mass murder 'coz y'know "they made me a monster". At the end of the day, while extraneous phenomena should be taken into account in analyzing a situation, the deed that gets done, usually is done out of one's agency.