I agree with you. As militia in the context of the framer's was local able-bodied men willing to defend the citizenery. It wasn't exactly voluntary nor were you drafted...it was simply expected that the citizens themselves would be able to defend themselves.
There was a time when having a gun & knowing how to use it was considered good citizenship.
We the people have relinquished that responsibility to a variety of others from law enforcement on up.
It's been a huge mistake. When citizens are no longer "capable" of law enforcement, they no longer keep tabs on the laws and true civil liberties take a dive (like letting your kids go for a walk unsupervised). We are raising a generation with no idea what it is to experience freedom to protect the license of the depraved and violent.