Designating one family member as being responsible for defense of all is a poor tactic. Even if every family member is supposedly supporting the armed defender, you are weaker than if everyone is taking actual, physical responsibility. You must make sure every family member is ready and equipped for defense.
The best way to keep from being harmed by the bad guys is to prevent them from attacking in the first place. Don't be a sheep.
You don't prevent them from attacking by becoming the bully, or by goading them into a fight, or by becoming what you claim to be preventing. And taunting them is just asking for trouble.
Telling your neighbor what he is allowed to own, or do on his own property, and backing up your demands with force or the threat of force, is an act of aggression. Invading his property to make sure he is complying with your meddlesome edicts qualifies you for a bullet to the head.
Really want "national security"? Then get rid of all anti-gun "laws" and disband the military. Anything else is just looking for trouble.