The significance of the militia, the Court continued, was that it was composed of ''civilians primarily, soldiers on occasion.'' It was upon this force that the States could rely for defense and securing of the laws, on a force that ''comprised all males physically capable of acting in concert for the common defense,'' who, ''when called for service . . . were expected to appear bearing arms supplied by themselves and of the kind in common use at the time.''
From here
The salient term is "the States" as political entities, distinct from the United States. You want the 14th Amendment to extend to restrict the states as they now restrict their police power in the area of morals? I mean how is the claimed right to be enforced? Against whom?