It's possible. I personally see him as a leftist riled up by months of cnn anti Trump hysteria and who may possibly be a leftist islam convert, double dangerous. Look at the victims, mostly white Country music lovers, besides a Trump event this would be a guaranteed place to target Conservatives. There have been multiple attacks against conservativrs in recent times, even a attempted assassination of candidate Trump at one of his events. Maybe he's just a disturbed person that wanted the thrill of killing.