The “District of Columbia”, once carved out of Maryland and Virginia, is a concept, not a sacred piece of ground. Change the boundaries so the actual district only covers the grounds of the White House, the Supreme Court building, and the Capitol grounds, and the triangular piece of ground that connects all three. The rest is ceded back to Maryland, as “District County”, and the residents of Washington and Anacostia are then represented by a voting seat in Congress, and rewarded by being represented by what are almost always two Democrat Senators.
The Federal government then pays the state of Maryland what would be the fair market real estate taxes on the Federally owned land and appurtenances that lie within this District County, on a decreasing scale, beginning at 100% the first year, and decreasing at 10% a year until the tenth year, when the program is discontinued altogether.
The District of Columbia scarcely makes up a decent TOWNSHIP, anywhere else in the United States. It barely qualifies as being a county.
Cede what’s left of DC back to Maryland but keep government buildings and spaces as Federally owned property. Then DC residents will have 2 senators and representatives by virtue of being a citizen of the State of Maryland.