Editor 's note : CNN Contributor Bob Greene is a bestselling author whose forthcoming book is `` Late Edition : A Love Story . '' Police tape surrounds the scene of a shooting in southern Alabama on Wednesday . ( CNN ) -- Carnage in Germany , carnage in Alabama , and one of the most saddening aspects of the killings is this : . The impulse to ask `` why , '' while present , seems somehow muted . There will be a search for answers -- why did Michael K. McLendon , the gunman in the American South , murder 10 people , why did Tim Kretschmer , the gunman in the German South , murder 15 people -- but even when a tentative answer is arrived upon , it almost certainly wo n't mean much . Because the real answer we 're searching for -- the answer that will stop these bursts of bloodshed -- seems destined to ever elude us . There is always an impulse to blame obscene killing sprees on outside stimuli . In the years just after World War II , comic books were cited as an incitement for young people to harm each other . Violent television programs were subsequently blamed , as video games sometimes are today . The connective theory has long been : if society desensitizes people to violence , if violence becomes a commodity , then it will proliferate . If people are passively taught that violence is everywhere , then violence will sprout , if not everywhere , then many wheres . But to place the brunt of the blame for this on outside forces is to duck a truth that we are understandably reluctant to face : the impulse to murder without remorse seems to be , in some people , almost like a learned language , deriving from somewhere deep and difficult to find . Thankfully , it remains relatively rare , although during weeks like this one it is not easy to take much comfort in that . Yet with each new torrent of killings , with each new demonstration that , to some among us , the idea of spreading heartache and horror is not only acceptable , but attractive ... With each new demonstration of that , we find ourselves once again looking for lessons , in a search that can seem perpetually futile . Are the gunmen in cases like these out to make a name for themselves ? If so , they are ordained to fail ; there was a time when multiple , random murders were enough to give the perpetrators such notoriety that their names became catchphrases . Charlie Starkweather , whose name means nothing to most people today , had more than one movie made about him after his killing spree on the American Plains in the 1950s . There was a time when we could ascribe , to people who murdered without mercy , a dark desire for the worst kind of fame . But that 's gone . Those names you read in the second paragraph of this story -- Michael McLendon , Tim Kretschmer -- may be freshly in the news today , but you will have forgotten them in a month or two . That 's one more numbing sign of just how ordinary extraordinary violence has become : the names fail to stick . The protagonists are interchangeable . How to stop this ? There has long been a debate over whether the death penalty is a deterrent to murder , but this week the murderers themselves are both dead , and almost certainly they considered that probability before they set out to kill . The learned language of violence seems to contain a concession , on the part of those who absorb it , that their acts may very well conclude with their own dying -- and that the price , in their minds , is acceptable , even , perhaps , sought . Which may be the most chilling lesson of all . Because if even death for those who do it is not enough to stop the profane slaughters around the globe , then our impotence in the face of this feels all the more profound . Whatever our need may be to grasp for answers , the killers , by dying on the day they kill , deny us the chance for even that scant solace . It 's the ultimate taunt ; it is as if they are saying : You want to know why ? You 'll never know . Which leaves us with only one certainty : . Before long -- in a matter of days , or weeks , or months -- we 'll be asking these questions again . The names will change ; the specks on the map will be different . But somewhere , someone who has learned the wordless language of spreading hurt and grief will do this once more , and we will pause anew in our daily lives to wonder what has become of us . And feel all the more empty at the silence that greets our question . The opinions expressed in this commentary are solely those of Bob Greene .
Bob Greene : The real reason mass murderers kill people is elusive . He asks whether outside influences play a role in inciting violence . Greene : These days , killers seeking lasting fame seem destined to fail . They are not motivated by the thrill of killing or even their own personal gain ; they don't have any other means of making money and