Teaching a child to shoot is not a bad thing. A normal child will learn to respect firearms rather than use them in a dangerous or deadly manner.
This individual was clearly mentally unstable and should never have been allowed near a gun.
"...And these atomic bombs which science burst upon the world that night were strange, even to the men who used them." H. G. Wells, The World Set Free, 1914
"The one pervading evil of democracy is the tyranny of the majority, or rather of that party, not always the majority, that succeeds, by force or fraud, in carrying elections." -Lord Acton