One of the cornerstones of liberty is the right to protect ones self, whether that be with guns, knives, lasers, guard dogs, bare hands etc. Once you stop people's rights to defend themselves, then the criminals have an unfair advantage.
"No freeman shall be debarred the use of arms." - Thomas Jefferson.
You quote a man I respect immensly, it's also a quote that belongs to a time and a situation that we in Australia do not even come close to replicating.