I like big arguments!
It must be proven that a gun in the hands of a baby is not a killing machine.
The army beat you to it: most armies issue guns but not ammunition to their soldiers, depending on their level of trust, lest they turn against the wrong people at the wrong time. For the average conscript combat soldier, this often meant that ammo was issued only right before combat, and retrieved after the action. This way, even though they have "guns", they are effectively neutered until their COs say they are not. For reasons of prestige and discipline, only Officers could carry a gun + ammo at all times.
Let me assure you, "having a gun" under these terms becomes more of a chore, and any fantasies of being some sort of super-duper action hero just because you have one soon fade away, marred in a thousand of regulations, inspections, and obligations. To the point that when you're actually given ammo, you are much more concerned with not displeasing your COs (e.g. your rifle jamming due to negligence in maintenance) than smiling in glee because "you shoot stuff".
If you ever did sentry duty, you'll be surprised at how complex, anal and almost anti-gun the rules of engagement are. A sentry is really expected to only be able to fire a warning shot as the very last thing he does before he's overwhelmed by an enemy attack, so all rules of engagement are designed towards this: ammo is often kept separate from the rifle even when on duty, accessing it is made complex by SEWING ammo clips into a tight cloth bag, and even then the first 3 shots are blanks.
On the converse, e.g. cops, armoured car sentries and bodyguards go around with live ammo, AMIDST CIVILIANS one chambered, and NO blanks.
TL; DR: other than that, the "child with a gun" argument is pretty weak: it stumbles upon the grey area of improper weapons (tools whose primary purpose is not as weapons, but which can take up that role just fun). Enter "kid with a gunpowder-powered nail gun", "kid with a large kitchen knife", "kid with a chainsaw", "kid with a blinding laser pointer", "kid with a bottle of vitriol" etc. or even just "kid with a can of spray and a zippo lighter".
Oh and BTW, the role of a self-defense gun should be primarily one of deterrence against violent things/killings happening TO YOU ;-)
Last edited by Maes on 01-11-13 at 11:02