So if we all carry a gun

then violence will be reduced? I don't think so but apparently Senator Leyonhjelm, the misnamed "Liberal Democrat", believes that there is no harm in relaxing gun laws.
Our present gun laws came about because the Howard government put them in place after the Port Arthur massacre where Martin Bryant acquired a gun through an advertisement and then went on to murder thirty-five people and injure another twenty-three. The laws may not have stopped Bryant harming other people but they would certainly have stopped him obtaining a gun with such incredible ease.
Gun laws are not going to stop determined criminals obtaining and using guns. They will do so without reference to the law. Laws may however make it more difficult for them to obtain one. That cannot be a bad thing. Laws can also make it more difficult for some people who should never  be in possession of a gun actually obtain one. 
In other words, laws won't stop gun related crimes and violence but they can do a lot to reduce it. So, what's wrong with that? 
I say there is nothing wrong with that. I am puzzled that a man who says he stands for "gay marriage" can oppose Medicare, our pharmaceutical benefits scheme, the increased tax on tobacco and more - including gun control. He says it is all about "individual freedom" but freedom does not imply the right harm others or prevent others from accessing services they need. 
I was talking with a cousin of the Senior Cat earlier this week. She was telling us about a talk she had been to in her aged care complex. The person talking to them is a woman in her mid-seventies. She has made many trips alone into the outback. She was asked about the safety precautions she took. One of the questions she was asked was, "Do you carry a gun?" Her answer was, "No, because it could be used against me."
That makes sense to me. Why would we want to potentially put ourselves in greater danger?