Permit me to speculate on motive. This was an attack on country western fans. Let’s look at them. They are all races but predominately white. Politically I think they are conservative as a general rule— no all but predominately conservative.They are predominately Trump voters=— not all but predominately and symbolically. They were attacked , The level of premeditation is beyond any question. If you are going to make an anti Trump statement what more representative group than country western Americans.
I am convinced the motive has been known for hours. No one goes to these lengths to commit suicide and shoot hundred of innocent people to die with a mystery motive. The motive is explosive and it is being covered up,in my opinion.