The relevance is that by maintaining the right to own a weapon, this was a deterant, such as today we use them to deter a home invader amongst other uses. You are reading too much into an example of why gun ownership can be important. Also, to say that we can't be invaded today because our lives are different is just being naive. There are also regulations, but that doesn't mean a thing to a criminal. Many of them use unregistered, black market weapons. That will never stop, just as the drug trade is still going on. Bottom line, if someone is against guns, they have the right to not own one, just as if someone does like guns, they have a right to own one. This country is too blind to see that wanting people to conform to their ideologies is not allowing freedoms that this country was supposed to uphold.
How can you say the gun market is just like the drug trade? We OWN the arms manufacturing market, a reason why tougher regulations will never come.