ROLL OVER, L'Enfant: Your plan may be virtually fulfilled, but what awful thanks you get from your fellow Frenchmen: They don't even put Washington on the top 10 list of cities they'd like to visit in the United States. In a recent poll, for every Frenchman who said he'd like to visit Washington, two lusted for Las Vegas.

Not that such lack of interest should be surprising: Washington does not rank as a top-10 American tourist attraction for German or Japanese tourists, either. The Brits, though, rank us ninth.

These statistics, buried in a Department of Commerce document, have not been shouted from the desk tops of the mythmakers in our Capital City. The line from them is that Washington has never been more alluring and the tourist hordes are on the way.

The fall of the dollar will bring European bargain hunters to the Land of the Free, they say. The shock of terrorist bombs will keep citizens of the Home of the Brave standing tall on their native shores. And because Washington has more museums than ever before, more art galleries, more restaurants and more hotels, it stands to reason that even more than the usual tribe of tourists will find Washington the place to be this summer.

Maybe, but there's a good case to be made that tourism peaked here in the 1960s. Consider these tidbits:

* Among Washington's most noted tourist spots, the White House, Washington Monument and Lincoln Memorial had the most visitors in 1964, 1966 and 1966, respectively.

* Although a 1984 National Capital Planning Commission report on tourism predicted a 3 to 5 percent annual growth in the number of tourists coming here, the figures are based on the historical increase in the number of visitors to the Smithsonian. Almost every year since 1945, more people have visited Smithsonian museums on the Mall. Yet a Smithsonian visitor is anyone who goes into any Smithsonian museum. A visitor who goes into every Smithsonian museum could get counted many times. Since 1965, the number of Smithsonian museums along the Mall has virtually doubled. There may not be any more tourists, just more counting of the same ones.

* A perusal of some old guidebooks to Washington reveals that there were just as many things to see a hundred years ago as there are today. For example, an 1869 guidebook, The Sights and Secrets of the Nation's Capital by John D. Ellis, was more than 500 pages thick. A turn-of-the-century newspaper article about Washington sights claimed, "There is scarely a block that does not contain some hallowed memory of a great deed done or of a famous man who marked the destinies of the nation."

* Although there may seem to be more hotels in the city than ever before and they may seem always to be full, the number of hotel rooms in Washington in 1984 was 17,559, not quite the 18,776 rooms available in 1960. The real hotel boom has been out in the suburbs, where in 1960 there were 3,701 rooms, and in 1984, 25,101. But according to folks at Gray Lines Sightseeing Tours, which sends buses into the burbs to collect visitors for downtown tours, many out-of-town hotels are full of businessmen. Gray Lines has learned not to seek tourists much farther away than the motels just across the District line. T OURISM promoters and planners here want to see more tourist attractions in the suburbs and more tourists all year long. Therefore, this year's slogan: Washington is "more than just a monument."

Paul Hall, who works for the Travel and Tourism Administration at the Commerce Department, says the idea of promoting Washington as something other than a city full of monuments could be a mistake: "They've done no market research. New York City knows exactly where and when to run their 'I Love New York' ads. And what to put in the ads, because they've done the research . . . Most of the 'Washington is a Capital City' ads were run in Washington. Great politically for the mayor, but not for tourism."

The Travel and Tourism Administration commissioned those marketing surveys overseas that showed what little regard foreign tourists have for Washington. The data also showed what the foreigners like about Washington: the museums, galleries and monuments. As Hall sees it, every ad that doesn't promote what tourists expect to like in Washington is wasted. It's a mistake to challenge tourists' preconceptions.

All of which probably would have pleased L'Enfant. He recognized that patriotic pilgrims would come to Washington anyway, so he designed the city with places for devotion: a monument to Washington, a Mall lined with the statues of heroes, each square dedicated to a hero from one of the states, a monument to naval victories and a national church between the Capitol and White House where patriots could congregate and sing the praises of their country.

In the end, only Washington, Lincoln and Jefferson got monuments worthy of worship. And all L'Enfant's sights for patriotic devotion, save the Washington Monument, were erased from the city plan before it was officially adopted. The Founding Fathers created a republic and they wanted their capital to reflect the essence of the republican ideology, a suspicion of power. And perhaps suspicious of the idea of soliciting tourists at all, Congress has forbidden government agencies from advertising the buildings and monuments they control.

So if you're among those Washington residents who have ongoing affairs with certain statues, paintings or pedestals devoted to prehistoric bones, don't let the hot air about tourist hordes keep you from your usual devotions. On many warm, humid summer nights, the ghosts around your favorite monument will, as usual, outnumber the tourists.