I was always under the impression that the purpose of DC was so that the seat of government would not be in or beholden to any state and that Maryland and Virginia could take their land back if it became a state since the agreement providing for the transfer of the land would be violated.
Yeah, but for years, DC wants to make itself a state. Notice in the beauty contests, contestants representing every state and the District of Columbia. There are other examples. However, if the fed govt pulled out of DC, it would be just another swampland.