That's regularly implied with nearly all shooters in America and it could be true in this case too. But a distinction to notice is that the kid obviously wanted to complete his mission before dying, and his actions don't indicate that would be possible.The kid did not care if he died
Suicide Mission
What shooter would expose himself to the police or the SS in broad daylight and try to gun down some victims?
Are Americans prepared to ask the important questions about their own?