This Constitution was written by the People of the several States FOR the united States of America. States are countries or nations. DC is not a State. It is not a country or a proper nation. The United States, which is the corporate federal body, is not a state, country or nation either. An allegiance to it is an allegiance to a corporation which exists in a federal district outside the union of American states. This Constitution does not apply there. It is OUTSIDE this Constitution, as are all the other federal territories and "protectorates."
DC, in my opinion, will never become a State because it would then have to conform to this Constitution.
US citizens, btw, have pledged allegiance to this corporate entity and are nationals of Washington DC, and are therefore not nationals of any of the States in union. This Constitution does not apply to them either, whether they live in DC or "reside" elsewhere.
Now you know the problem.
~ Engage in the war of attrition: http://pacalliance.us/redamendment/