The decades-old image of the Washington area as a bastion of antiunion political and corporate activity, barely distinguishable from the Deep South, is not as accurate as it once might have been.

For many years, the public and the city's work force seemed as far removed from strikes and picket lines as it is from industrial centers like Detroit or Pittsburgh.

The image and essential reality is changing, as a result of the continuing spiral of inflation, the growth of the local economy, particularly in the retail field, and the emergence of large-public employe unions.

Just within the past year, the area's largest union, Local 400 of the United Food and Commercial workers International Union, has become increasingly visible. It won the right to represent almost 6,000 employes of Woodward & Lothrop department stores, shook the local retail picture by striking the prestigious Raleigh Stores Inc. clothing chain and moved slowly into the locally uncharted waters of banks and health-care facilities.

"The Raleigh's strike," says Local 400 President Thomas McNutt, "demostrated the change in the people's attitudes.I don't think that 10 years ago we would have gotten anything like the kind of support we're getting now."

McNutt and Raleigh's union members confidently believe that their steady picket lines kept thousands of customers from shopping Raleigh's during the month-long strike last spring, a local show of union support with little precedent.

"There is more awareness than ever before here about the importance of the labor movement," McNutt said. "Unless something fantastic happens to the economy and as long as inflation touches all people, workers will try to respond and protect their incomes no matter what industry they're involved in."

Local 400 may have yet another opportunity to show its muscle when contracts affecting 15,000 food workers at the area's leading grocery store chains expire on Saturday. Talks on that contract will continue this week.

According to the Greater Washington Central Labor Council, there are about 260,000 members of unions associated with AFL-CIO in the area, figures which do not count independent unions, such as the Teamsters, autoworkers, police unions and organizations that represent employes of particular government agencies. Public employes make up just under a third of that total, with food, retail, restaurant and hotel workers adding about another 65,000 workers to the total, according to the council.

Throw into the membership picture of local unions the possibilities that emerge from the size of local union pension funds and it is clear that the labor union picture in the Washington area is anything but sleepy.

And in the future, the financial power of the local unions, like Local 400, may become even more significant. McNutt, president of Local 400 since 1975, says his group, in conjuntion with local building trades unions, has begun working on a plan that would invest the organizations' pension and other funds in companies and other institutions that meet with the unions' social and political goals.

Local 400 and its counterpart in the Baltimore area have a pension fund of close to $100 million, McNutt said. "We want to steer all the money we can into good social investments," he said. "We want to use that vast pool of money to the advantages of our members instead of pouring it into nonunion activities."

If those unions ultimately put together such a plan, the impact on the local banking and corporate communites could be enormous.

Nevertheless, Washington will never be a conventional union city. Lacking an industrial manufacturing base, such as the work force in nearby Baltimore, local unions must by the very nature of the area represent the more affluent, white-collar workers that caused area shoppers to marvel during picketing outside Raleigh's stores this year.

Although there have been some attempts by economic development officials in local governments to add to the area's limited manufacturing and industrial base, most planners predict growth of the area's job market is clearly dependent on other types of business expansion, most of it white collar.

Between 1979 and 1982, the number of manufacturing jobs in the area is expected to rise 2.4 percent a year to 56,350, still less than 3 percent of the area's job pool, according to a recent study by the District government's Department of Employment Services. Although the annual growth rate will be slower -- only 1.8 percent -- government jobsw will total 467,370 by 1982, the study said.

At the same time, however, the services sector of the local economy, including hospitals, schools, business and nonprofit organizations, and legal services is expected to grow by more than 4 percent as those industries will supply close to a half million jobs to Washington area residents.

Similarly, between 1976 and 1982 the numbers of jobs in the finance, insurance and real estate fields will balloon from 82,030 to 101,160.

Therefore, it is clear that the targets for union activists in this area must be economic areas that are traditionally nonunion. Although Local 400 recently won the right for the first time to represent workers at a local bank, Hemisphere National Bank, only 30 of the nation's 14,000 banks have union employe contracts. This month, Local 400 has scheduled a vote at an area nursing home to unionize that institution's nurses. s

Despite the visibility of the recent retail activity and last month's major public employes' strike against Prince George's County, some union officials say the fights on those fronts have just begun. In particular, building service and clerical workers, to name just two work force segments, would seem to be likely, if reluctant, targets of union organization.

"You have to understand those people are afraid," said Joslyn Williams, director of the Central Labor Council. "They're afraid to sign a union card and are afraid to even apply to the NLRB (National Labor Relations Board) for a vote."

Clerical workers traditionally have been hard for unions to organize.

Despite generally low wages and a lack of fringe benefits and job security, these workers have tended to view union membership as "unprofessional." In addition, many of the clerical workers in the area are recruited from smaller, more rural areas where pay scales are lower. And corporate employers in the Washington area are forced to compete with government pay for clerical help.

The effort of local unions to organize the area's white collar workers will not be a simple matter either. Earlier this year, the Office and Professional Employees Union, which already represents workers at some of the nation's largest insurance companies, made a major effort, coordinated by the union's New York office, to put a union together at Geico.

Indications are that the action has faded with little or no talk of an election there any time soon.

"I don't think they've been making much of an impresion on our employes," said a Geico spokesman, who describes the insurance company's workers as being happy in their suburban-like quarters with free parking and substaintial benefits. Representatives of the union would not comment on the Geico situation.

Even give the fizzle at Geico, there is little doubt the office and white-collar worlds hold much of the future for unions in the metropolitan area. Washington's own Norma Rae might have an MBA.