How about the absolute failure of the NZ police in stopping this guy?
Nearly 10 min at the scene and he could still casually run back to his car, put his weapons away and drive off.
Blame everything but the obvious. FWIW the Las Vegas shooting went on for 15min and the police didn't get to Paddock for over an hour.
Guns could stop existing tomorrow and humans would still mass murder each other.
There was also draconian gun ownership laws in NZ already, did that stop this?