What a terrible, senseless, cowardly act. My thoughts go out to the people who have been impacted by this, those mourning the loss of family, friends, colleagues. As always, the heroic acts of some will help to fuel hope and optimism for a better day and restore our belief in humanity in the aftermath of such an inhumane act.
There are no excuses for this man's behavior and to blame it solely on his religion is far too simplistic. Clearly he has had issues with others in his day to day activities, and although quite possibly his religion could have been a motivating factor, but no real sane person could have committed that sort of act solely on the basis of his religion. Yes, there are some psychiatrists who need more help than their clients, just as there are some judges/police officers/government officials who are more corrupt than those behind bars.
This man was born and raised in America, educated in America, trained as an American soldier and served for several years.
I suspect that once people start to delve into his psychological profile, once he is poked and prodded and interviewed and his life and those of his family/etc are examined, we'll find out that he likely fits the profile of other disgruntled mass murderers who have gone to their places of employment/public places and killed and/or tried to kill as many people as possible.
Religion may very well be one part of the motivation, but it can not be the sole reason for him doing this- otherwise no person raised as a Christian, for example, could be capable of commiting crimes/atrocities of their own... could they?
It's quite possible that this American Muslim joined the miltary as many others have, to obtain an education, never really believing that he would have to go to another part of the world and actually kill people. He was lokign at his first deployment and after some time of counseling/listening to people who have been there, he more than likely hoped that with his out int he open ramblings/etc, they'd discharge him from the military and he could leave with his education in tact- but it appears as though he was being shipped over. Add to this his religioous upbringing and other frustrations in his life, and it could very well be that it was this man's PERSONALITY deficits that contributed more to his decision to kill than his religion.
At any rate, people will debate their varying beliefs. People will blame his religion, or blame that he was being picked on. People will blame the politicians-- Bush, for sending the troops over there, and Obama for not pulling them out like he said he would and the ongoing stress on military personel, etc. This will not bring the deceased back, this will not at this moment comfort the families, and this will not help make children on other bases around the world feel secure that their mommy's and daddy's are safe when they're at home.
Just a bit of a rambling post- trying to make sense of it like everyone else.