It comes naturally to think of Franklin Delano Roosevelt as an architect. Not specifically, of course, not as a mere designer of buildings, but in a grander way, as chief designer and final planner of vast, necessary changes in the nation's political and social landscape--the architect of the New Deal and of allied victory in war.

And yet as Brain Truster Rexford Tugwell recalled, Roosevelt "felt in himself a talent for design," and he never demonstrated much compunction about exercising this talent upon buildings in the family estate at Hyde Park, N.Y., at the summer retreat on Campobello Island, at the health spa in Warm Springs, Ga., and in Washington.

Roosevelt's involvements in architecture caused a few lively public spats in his time as president -- most notably perhaps his vigorous fight to have the Jefferson Memorial look precisely as it does today in precisely that spot. But his architectural efforts are mostly forgotten or overlooked or humored as the meddlesome tinkerings of a great and powerful man. Nonetheless, it is clear that he had a big effect upon the physical look of the capital city.

To honor the 100th anniversary of FDR's birth the National Building Museum has organized a series of two-mile walking tours that dramatize the scope of Roosevelt's architectural interests in the city. The tours include stops at the Federal Reserve Building, the annex of the Pan American Union, the Department of Interior, the old Executive Office Building, Lafayette Square, the White House and the Federal Triangle.

Even this extensive itinerary does not fully capture the range of Roosevelt's special interest in the capital, for he reviewed, and sometimes changed, the plans of almost every government building that went up during his long presidency, and he stepped into quite a few disputes concerning private building projects as well.

William B. Rhoads, an architectural historian at the State University of New York in New Paltz (right across the Hudson River from Hyde Park), has made an extensive study of Roosevelt's numerous excursions into architecture. He points out that Roosevelt did not come to town in 1932 with a grand city plan in mind. Rather, in most cases the president responded to existing designs or projects -- the Federal Triangle, initiated under Hoover and completed during FDR's presidency, is the biggest example of this.

Nonetheless, there are a couple of notable exceptions. In the architecture books the design of the Bethesda Naval Hospital is attributed to Frederick Southwick, chief architect for the Navy, and Paul Cret, the Beaux Arts architect from Philadelphia. This may be correct in the technical sense, but Rhoads says there is no doubt that, at heart, "it was the president's design." Roosevelt objected to the original, conventional design for a five-story hospital building. When he made a sketch for the 15-story set-back tower we see today, the Navy and Cret, in effect, said, "Yes Sir!" to the president of the United States.

The evidence is not so definite concerning Roosevelt's involvement in the design of National Airport, but Rhoads believes it strongly suggests that the president himself is responsible for the columned portico, which he wanted "to call up memories of Mount Vernon." (If this story is true, the president was clearly proud of his handiwork. In his speech at the dedication of the building he called it "perhaps the most beautiful airport building in the world.")

Even on projects in which he was not so directly involved, Roosevelt made his preferences known -- and felt. Pearl Oxorn, who prepared the informative materials for the walking tour, shows at several points along the way (Cret's elegant Federal Reserve Building, Waddy Wood's Interior Department, Edward Bennett's Federal Trade Commission building at the eastern end of the Federal Triangle) how Roosevelt's architectural conservatism, combined with his politician's wariness of extravagant spending on building projects, made him veer toward a leanly ornamented, less expensive "classical" style.

Anyone who likes these buildings might politely call the style "stripped classicism" or "art moderne." Those who don't are not above calling it "fascist architecture." There's something to be said for both points of view--a sort of modernism in classical dress, it represents a compromise that was, in fact, an international style for public buildings during the 1930s, a style made infamous by Hitler and Speer.

Still, the finely tuned scale and urban propriety of Washington's New Deal buildings bear scant ressemblance to the theatrical gigantism of the fascist architects. It is a small point to make, or perhaps an obvious one, but these distinctions say a lot about the differences in aspiration and character between Roosevelt and Hitler, who was, of course, even more of an architect manque' than FDR.

In architecture as in politics Roosevelt enjoyed a good fight. In 1938, when a design for a cottage at Hyde Park was published in Life magazine with the signature, "Franklin D. Roosevelt, Architect," John Lloyd Wright (son of Frank Lloyd Wright) overresponded: "Put me in a concentration camp. The moral breakdown of the integrity and dignity of the architectural profession seems now complete." Roosevelt quietly backed down.

Fortunately, too, Roosevelt's distaste for the "blots and blemishes" of Victorian architecture did not extend--for reasons entirely beyond his control--to the destruction of the Old Post Office Building or the remodeling of the Old Executive Office Building. Roosevelt may pick up some preservationist demerits for supporting those schemes, but he rebounds with honor at Lafayette Square, which he saved in 1942, precisely 20 years before President Kennedy stepped in to save it one more time.

Mostly, of course, Roosevelt won his fights. He greatly admired John Russell Pope's design for the Jefferson Memorial and he wanted it to be placed exactly on a north-south axis with the White House. What he liked, he got, but not without a tremendous outpouring of opposition from all sides: The Commission of Fine Arts opposed the location and the design, conservative architects attacked Pope for repeating himself (he already had designed a similar dome for the National Gallery of Art) and modernists such as Frank Lloyd Wright called it an "arrogant insult to the memory of Thomas Jefferson."

A group of female conservationists even threatened to chain themselves to cherry trees that were threatened by the memorial construction. Exhibiting characteristic fire, Roosevelt responded, "If the tree is in the way, we will move the tree and the lady and the chains and transplant them to some other place."

Today these cries seem like ancient echoes. The Jefferson Memorial, though not so moving a monument as Henry Bacon's Lincoln Memorial nor so taut a building as Pope's own National Gallery, has aged well. And it is situated perfectly. In his superb book, "FDR: A Centenary Remembrance," Joseph Alsop puts the story in perspective:

"I had always wondered why the Memorial meant so much to Roosevelt until I dined one night with President Kennedy and chanced to note how perfectly the marble neo-Greek structure closed the vista from the White House, in the exact manner of an English grandee's 'folly' temple closing the main vista through his park . . . In some sense, Roosevelt regarded Washington and its environs as the President's very own . . ."

It would be small-minded indeed to resent this sense of possession. In this case as in so many others Roosevelt stood on surer ground than his critics. On the whole his long, detailed involvement with the city of Washington had benevolent results. Roosevelt clearly had a profound faith in the city as a lasting symbol, as well as the working capital, of a great democracy.