Hey, I'm fine with the argument "guns don't kill people, people do." So if Aussies never had a mass shooting epidemic prior to the ban, and the ban is correlational at best in preventing more Port Arthur style massacres, this perhaps suggests Australians are responsible gun owners and/or more mentally stable than Americans? If we used the criteria from your posted pictures (including drive bys and gang fights), the US count would be in the thousands, not the dozens like the Aussies here. So maybe it's not guns that are the problem, but guns plus Americans that are the problem? After, we're the most pilled up, physically unhealthy, drug addicted nation in the so-called 1st world.
I've always felt that way to an extent, that Americans in general are too irresponsible/mentally unstable to honor the privileges the 2nd amendment affords. Proof is in the pudding here. Why didn't any other country have a mass shooting epidemic like America when gun control was more lax?