Sorry I missed this post earlier, but you are correct. Those who drafted the Constitution were smart enough to realize that they didn't know everything, and spelled out procedures to make changes or additions. The problem now is that the Constitution is often just ignored, in order to avoid the (almost certainly, I hope) futile effort to make the changes necessary to deny certain rights.
I case I come across as advocating a repeal of any Amendment, nothing could be further from my mind. It's just a bit frustrating to see our Constitution trampled on by lawmakers, who are encouraged or at least allowed to do so by us, without any regard to the consequences.
I believe that if, the right to bear arms is no longer credible in the America of today , and we allow ourselves to be dis-armed, we will deserve it when we lose other rights that the second Amendment enables us to protect.