For the District of Columbia, the latest news from the Commerce Department on retail sales is not bright.

While nationwide sales at department stores in June were up 9 per cent from the same period last year,and sales at 95 department stores throughout metropolitan Washington rose by 10 per cent, business at three major downtown stores declined by 4 per cent.

For the first six months of 1977, the pattern is similar. Areawide sales up 10 per cent in generally a good year for retailers, but down 2 per cent in the city's old downtown business district. The city's economic malaise is continuing.

To be sure, other troubled metropolitan centers are experiencing weakness in consumer buying and a subsequent loss of tax revenues, leading to cutbacks in basic education and public services.

What is surprising , however, is how long the District's economic life has been permitted to go down hill.

It is easy to assess blame for the absence of new business in the city, the flight of companies to the suburb and high unemployment in the city. The federal government, the District government and the area's District government and the area's business community all have played a role. More properly stated, all have ignored the District's economic needs, year after year.

Until very recently, top leaders of the city government have shown little interest in business development here - an aggressive program to attract and keep business, such as that practiced in Fairfax county.

Congress has been reluctant to approve budgets for economic development. Why should the representatives from New York or Chicago rubber-stamp a program that could end up robbing their states of jobs?

As for the so-called local business community, there is none. Instead, there are many local business communities - one for Fairfax County, one in Prince George's County, and one for every other jealous jurisdiction. There are some major corprations that prefer a national identity and are seldom involved in any local problem.

The Metropolitan Washington Board of Trade, by far the largest and most representative area business organization, itself seeks economic advance for the area as a whole and not the District alone. Yet, ironically, suburban chambers of commerce are convinced that the Board of Trade pays too much attention to D.C. problems.

There is big business in the Washington area - Southern Railway, Allegheny Airlines, Martin Marietta, Mars. Inc., Government Employees Insurance Co., Marriott Corp., for example - but these companies have not been organized as part of a coherent group to view the District's lack of economic muscle as a problem worthy of attention.

For these reasons, it has been evident for some time tht any serious effort to to bring new business and jobs to the city itself must start within the District government.

It's not pleasant ot pick a fight with suburban neigbors but District Mayor Walter E. Washington's administration now appears committed to that course of action - after years of pressure from outside his administration.

Last April, Washington established for the first time an Office of Business and economic development. Although a director still has not been named, an appointment is expected this fall.

More important, the incoming director already has a "Blueprint for Action." which should mean that work can begin immediately if the District government means business. There will be no necessity for the new director to study the problem and draw up priorities.

A draft of the "blueprint" now being circulated, was prepared by an economic development advisory committee consisting of 23 private and 11 city leaders. Most of the private sector members are representatives of various civic groups, universities or consulting organizations. Not one is a spokesman for a major corporation based in the area.

The blueprint is a typical consensus document and contains little that is new, in terms of ideas for economic development within the city or assessment of decline.

But, as one committee member said privately, it is a workable plan with a "lot of positive thoughts," The key is its implementation. If the Mayor can attract to the new job a person with sufficient clout, and if the plan as outlined is followed, the city soon would begin to experience economic benefits.

More specifically, the plan sees the District as the region's primary retail center: the center for finance, education and other services: a more significant and international headquarters city: a national information and communications center and a cite for research and development firms.

The blueprint views a proposed convention center as a lynchpin for the city's future health, as do most of the District's business leaders. The blueprint also assumes an increase in the building height limit from 130 to 160 feet in a limited area downtown and the ability to issue commercial and industrial revenue bonds.

Carrying out the program, the blueprint emphasizes, will require participation by 11 D.C. government organizations. That's a difficult task of administration.

Once again, Congress must act if the plan is to be implemented fully. Congress must approve borrowing authority for construction of the convention center, an issue currently unresolved. Congress must back Home Rule charter amendments to permit D.C. to use commercial and industrial revenue bonds, development tools used commonly by suburban counties. Congress must approve the proposed increase in height limits for downtown buildings.

Given the record of Congress and normal lack of interest at the White House on D.C. affairs, these actions won't come easily for the D.C. government. There is no evidence that the whole area business community is wildly enthusiastic about any of the ideas and willing to invest lob-buying power.

But, at least, the D.C. government has set a course of action foritself. And that's where it must start.