While some folks (liberals) would be shocked by this poster, I think it is more shocking that so many young people today have no first-hand knowledge of firearms. That's not to say that everybody should own one. That's a personal choice. However, guns are such a powerful force for both evil and good that to deny yourself - or your kids - an understanding of them is foolish.
My Dad enrolled my brother and me in an NRA shooting class back in the 1960s. I'm thankful for that, because it taught me to respect guns and not think of them as toys -- as most kids do, sadly. Learning how to handle a gun did not make me want to wield one, and I have never actually owned a firearm. Guns have been a fact of life for some 500 years. To not want to learn how to use one is foolish. It fits the definition of "ignorant."
Even if you never plan to drive a car, you should learn how to operate one -- just in case you ever need to. Cars kill, too, but you want your children to know how to drive.
Note: I would credit the creator of this poster, but it seems to be one of those many items these days that has been reposted so often that the origin is murky at best.