Why couldn't they? There were already state governments and some might suggest that state governments are more corrupt than the federal government ever would be. I also question any suggestion of moral bankruptcy without further description of what is meant.
The military isn't mentioned in the 2nd amendment; the militia is, which were state troops. Remember also that militias had existed long before there was a national government. Remember too, there was a national government before there was the constitution.
Shoot low, sheriff. They're riding Shetlands!
Underneath the starry flag, civilize 'em with a Krag,
and return us to our own beloved homes!
Buy War Bonds.