Because the District of Columbia is the seat of the Federal Government and has become the urban center of a rapidly expanding Washington metropolitan region, the necessity for the continued and effective performance of the functions of the Government in the District of Columbia, the general welfare of the District of Columbia, the health and living standards of the people residing or working in the District of Columbia, and the conduct of industry, trade, and commerce in the District of Columbia require that to the fullest extent possible the development of the District of Columbia and the management of its public affairs, and the activities of the departments, agencies, and instrumentalities of the Government which may be carried out in, or in relation to, the other areas of the Washington metropolitan region, shall be coordinated with the development of those other areas and with the management of their public affairs so that, with the cooperation and assistance of those other areas, all of the areas in the Washington metropolitan area shall be developed and their public affairs shall be managed so as to contribute effectively toward the solution of the community development problems of the Washington metropolitan region on a unified metropolitan basis.