All Dog and animal owners must realize that our pets are our responsibility and if your pet is big and strong enough to hurt another animal or person then you have a great responsibility. Yes, a strong dog can protect you and they can be controlled properly, possibly, but. Dogs like people can go 'off the handle' sometimes and it is a bit unpredictable.
Separate from the law, how old could a child be before you would let her or him safely carry a hand gun around your house or in public? 10, 11 , 12...? Older?
Well, the fact is that many dogs (and certain breeds) commonly have the jaw strength to do far greater damage than a hand gun. Many can cut through bone better than a bullet and they don't stop coming the way a wild child might when they hear the gun fire.
Think of your strong pet as a child with a gun.