we're in a patch where people are trying to kill as many people as possible, very frequently in very many places, in the name of many different ideologies, or because of many different pathologies: for any reason or none. the question begins to occur, whether people are engaging in mass killings because of their beliefs, or whether they're cultivating beliefs in order to justify engaging in slaughter. the pattern of behavior is similar, whether it's islamist radicalism, white suprematism, a disgruntled employee, a fundamentalist christian going after planned parenthood, a bullied student, a schizophrenic, or whatever it may be. perhaps people look for a way in, something to justify their radical break with the species. or at least, the causation - the interaction between beliefs or illnesses and actions - might be complicated, for while the motivations or causes for the killings are various, the patterns of behavior are relatively repetitive, stylized, salient. it is the act of mass killing and the technologies that make it possible or articulate its forms, rather than the reasons or psychology of the killers, that is characteristic of our time.
it may be that you informally suppose that human beings are social creatures, that there's nothing worse than isolation, and that pulling together for unity is the very essence of human goodness, where we should go or even are going in the slow victory of progress. but, on the other hand, 'the social' is dark, dark. other people all around you, at the office, on the strip, in trains and planes and automobiles, can be extremely difficult in a million ways: this is truer of the people close to you than others. really both are true: we feel the urge to unify, and our unifications are incredibly problematic and oppressive.
some people love a crowd. and some people feel profoundly claustrophobic in a crowd. some people are happy to agree with their friends; some people constantly feel constrained by the epistemic and a thousand other social constraints. this is the reality of us. from cradle to grave, people might nurture and assist you; they might break you down or oppress or destroy you pointedly, or they might spend your whole life pretending you don't exist at all. i do think a lot of these people have reached the point where they were negating the whole species, in all of us and in themselves, where they reached the (bent?) judgment that we, all of us, homo sapiens, are better off not existing than existing. whether we deserve to exist: i think that is an open question, myself. but once you become certain that we don't, you may have released yourself to attempt maximum destruction. (actually i think that the right response is a hearty yet despairing belly-laugh.) then you might be asking yourself: ok, where's an opportunity, or what's a justification, etc?