Lone wolf?

Twelve Thirteen dead, dozens more injured. Early reports were that the shooter was dead. Hours later we learned that despite being shot numerous times, he's alive and in stable condition.

I find myself glued to the cable stations. All of them.

A former co-worker, Matt Mulcahy, detailed in his blog how Twitter and other digital platforms covered the story.

Here in Kansas City, we rejoice that one of our own was injured, but survived the shooting.  Through her family, we learned that she was in the classroom when the shooting started.  She and her fellow soldiers dropped to the floor and covered each other.

But why?  What drove him to turn on his comrades?  A doctor is not supposed to kill.  Some are calling the rampage the work of a "lone wolf."