Ooh, this manages to be an example of several fallacies at once. Let's examine them.
1. Red Herring. The original quote was satirizing the comparison of guns with locks and guard dogs, when clearly the relevant difference is guns KILL PEOPLE. No mention was made of guns being the cause of The Fall or whatever.
2. Straw Man. Again, if I had said anything that implied that guns were the cause of violence to begin with, then this would be a viable piece of sarcasm. I didn't, so it's a misrepresentation of my views.
3. False Dilemma. The implication is that because there was violence before guns, adding guns makes no difference. This is patently and obviously false.
Good job! I hope you pull this out again when somebody invents a biological weapon that anybody can cook up in their back yard, and spout it with your last gagging breath as the human race goes under. (Your turn - I'm sure I violated SOME rule of argument there.)
Incidentally, serious question: if the second amendment covers automatic weapons, what doesn't it cover? Does it cover a suitcase nuclear weapon? What if I don't feel secure without it?