This is not just some natural disaster. It can be prevented, if you want. If you don't, admit that.
And I suppose that you can cite your country's banning of significant reduction of guns over several decades and subsequent elimination of all massive decline in gun crimes as proof.
Absolutely.
http://www.time.com/time/world/article/0,8599,1736501,00.html
We should not pretend that Howard was the only guy to do anything about firearm-related deaths. Even before Port Arthur, a bit over 7% of Australians (as opposed to something like 50% of Americans) owned a firearm, declining by 3.5% a year, hence the already-low death toll (one-fiftieth of the US, according to Snopes).
But Howard's reforms probably did have an effect:
http://sydney.edu.au/medicine/news/news/2006/Dec/061214.phpDid the ban actually work? Well, it was actually designed to reduce Batman-style massacres, not regular gun crime. The number of people killed in massacres declined from 121 in a decade to 0 in a decade. That's the most statistically significant measure of the policy's success you can find.
http://www.crikey.com.au/2008/09/09/what-john-howard-could-teach-the-us-about-gun-control/Criminals have stopped using guns in robberies, according to the ABS. Gun suicides have declined at double the national rate, even though the reform was not designed to have this effect.
But, as I emphasised in the post you responded to, Australian gun regulation is not a single law. When Victoria reformed gun laws in the 1980s (and no other state did so), gun crime reduced relative to the other states.
http://injuryprevention.bmj.com/content/10/5/280.fullGun ownership by 1996 by 1996 was already low. I can't find historical stats, but it seems that gun ownership was low early in the cold war, increased in the 70s and early 80s, and then declined from the late 80s until now. So you can't point to a single law half-way through that process and say it failed. Australia did have a low rate of gun ownership and a corresponding low rate of gun crime already, even in 1996.
Like I said, if you are willing to pay the cost of regular gun massacres for the value of 'freedom' and 'protection' against an evil state that would totally kill everyone except for a bunch of Kentuckians with .22s (seriously, I've heard this argument more times than I can count), that's fine. But admit it. Gun crime is the cost you pay for 'freedom'.