Each man must decide for himself if the presence of a firearm is worth the risk when he has children around. This is my approach and experience:
I will state that I firmly believe that if a gun is to be depended on for the defense of family and self, the most important consideration after making sure that the gun is dependable is that it be IMMEDIATELY accessible. This infers that it is LOADED. The miserable maggots that prey on innocents today are the most cowardly creatures that crawl God's good earth and will strike only when they are sure that one's defenses are down. Those of you who hunt can better understand. How many birds or deer have you missed because that gun was not ready; the safety was on, your heavy clothing preluded your getting the gun on target quickly, the chamber was not loaded, etc.?
The readiness of the defense firearm, with it's inherent hazard or even danger to children (and the MANY stupid adults we must contend with) is apparent. I claim that one can hold the risk down to merely a hazard to which even well trained and responsible people subject themselves when they use guns (or drive a car, etc.) and eliminate the danger by training, coupled with other well practiced disciplines.
My approach was to start each of my five children with a BB gun at the age of four. The cheapest little Daisy was used (model 105) and the kids all loved it. At five years of age they were all introduced to both the Crossman air rifle and a cut down .22. During this period I made a constant practice to make myself immediately available if any one of the children wanted to look at one of the many guns that they knew I possessed. This included the occasions where one of them would bring Johnny or Mary from next door to see a gun. I did not make an exception to this practice no matter how busy I was or what I was doing. Rarely did one of them fail to satisfy his curiosity in a few minutes. Satiating their curiosity in that manner effectively precluded any of them sneaking in to play with a gun.
If I handed them a firearm to examine without opening the action, and they did not refuse to accept it without my doing so, I made them think that all hell's fury was upon them. When I asked them if that particular gun was loaded and they did not respond with "Of course, all guns are loaded and should be treated as such" hell struck again. Each was taught that if he saw a gun laying ANYWHERE to tell an adult and not to touch it unless (as they got older) they were familiar with that PARTICULAR gun.
To test this last bit of theory, I would occasionally lay a pellet pistol on the dining room table, and from an inconspicuous position watch for the reaction from the kids. I was encouraged when, at five years of age my most spastic spied the pistol, walked around the table twice while pondering the gun, then came flying through the house yelling "Dad, there's a gun on the table."
The reason I started the children at four years of age was because that was the age where each began to show interest in "real guns". Up until that time the two boys had their own toy guns and the three girls had virtually no interest until then. Since the attention span of young children is short, training sessions were short and any sign of boredom or restlessness signaled to me to end the session.
Each child was presented with his own .22 rifle at 7 years of age with the understanding that it would be handled in only Dad's presence until they were old enough to show the responsibility needed to go it alone.
During these years, thanks be to God, I had no scary occurrences.
As for general discipline, I make a practice of putting the chosen gun in a bedside pouch each day as it gets dark, (the flap fits between the mattress and the box springs) and lock it up in an out of sight area of the garage each morning when I first go out the front door. This last is done so that I will never have to come home to face my own gun. If someone is to be in the house all day, the gun remains in it's bedside pouch. We have a rule that no one outside the immediate family is allowed to enter our bedroom without express permission.
The neighborhood kids are trained by me that no one is allowed inside our garage until he "gets older" because there are dangerous tools there. At the risk of having irate parents angry with me I have, on occasion, impressed upon their fannys or a twisted ear, that I am quite serious when I speak. Parents have not ever objected. It turns out that the grumpiest guy in the neighborhood is the one that they come to with broken toys, smashed up bikes, etc., as they get older. My Dad did the same thing and he was also the man who could fix anything.
My kids now range from 22 to 29 with no fear of firearms and having suffered no unfortunate -- or even scary, experiences.
My 29 year old daughter can outshoot at least 90% of our police although she has no particular interest in firearms other than to show she cannot be outdone by mere males. The battle of the sexes is still healthy and active in our family. Great fun! She is still trying to muscle in on our yearly "men only" high Sierra hunting trip.
By coincidence, my oldest daughter and I were discussing this method of gun proofing children. She pointed out that it was successful because my wife and I insisted on absolute obedience from our children - that those who are not obedient may not benefit from, but rather become victims of, the above approach. If you are in control of your children the above approach is probably a good one - if they are in control of you, gun problems are down in the noise.
I have seen much expounding, here, of teaching children not to point toy guns at anyone for fear they might do the same with the real thing. This is a waste of time. They will point toy guns at their little friends anyway. My experience (my own childhood and with that of my five children) is that the two are very clearly differentiated in their little minds and that there is no confusion as to which is real and which is toy. When children play cowboys and Indians - or war, they do not associate "bang, bang, you're dead" with death, but rather with the simple game that it is. The only lesson that I attempted to instill was that they must care for their toy guns just as they would any other possession. It was the beginning of learning to keep track of, keep clean, and keep maintained all of the possessions that came from God through their parents.
As was my father, I was a stern disciplinarian, but have always believed that there are enough things that one must get after kids about without wasting time on imaginary troubles. My five are shining examples that this philosophy really works.
Expect a lot, but LET THEM SET THEIR OWN TACK. You will never be sorry.