But while the O.S.S. is known for its intelligence-gathering operations and its dissemination of propaganda in enemy territory, its perhaps least heralded legacy is in the field of design. Crucially, the organization had its own dedicated design branch — renamed the Presentation Branch in 1944 — that oversaw the creation of graphics, maps, slides and short films about the war effort. (The design historian Barry Katz outlined this history in a groundbreaking 1996 article in the journal Design Issues.) These served various purposes, as requested by members of the military and Department of State. The Presentation team, often working with Research & Analysis and other O.S.S. divisions, explained the diet and nutrition of German city dwellers in order to help the United States government better understand the enemy; illustrated the correct use of weapons, like knives and grenades, and created models of weapons; detailed Japanese “superstitions” for the purposes of psychological warfare; and sent cartoonists to Indonesia to make studies of local iconography that could serve as anti-Japanese propaganda. For these efforts, the O.S.S. would draw on the expertise of an astonishing number of designers from across disciplines: Raymond Loewy, Henry Dreyfuss and Walter Dorwin Teague, who had all recently worked on the 1939 New York World’s Fair, with its focus on “The World of Tomorrow”; Walt Disney, the most powerful creator of animated myths in the 20th century; Lewis Mumford, an architecture writer for The New Yorker and an unsparing critic of modern technology; Orson Welles’s assistant on “Citizen Kane”; the designer of the Q-Tip box, who also — in his capacity at the O.S.S. — led the team that designed the logo for the United Nations.

The look of these projects was subsequently so absorbed by postwar America, and by the private sector in particular, that it remains easy to overlook the Presentation Branch of the O.S.S. as a birthplace not just for contemporary design as we know it but for the way we now conduct professional life. The O.S.S. pioneered the use of visual displays in conferences, now such a staple of business and industry that it’s hard to imagine them having an origin story — namely, at the War Department conference at the Pentagon in 1943, which convened business and labor leaders to get them onboard with the total war effort. The basic template of instructional pamphlets and posters — the kind you see on every airplane or near every fire exit — is also a feature of O.S.S. iconography, which offered minimalist, illustrated instructions on how to use a knife against a Nazi in hand-to-hand combat. With the Nuremberg Trials, for which the O.S.S. designed the courtroom — the placement of the military guard, the solitary witness box that made a testifier look guilty, the graphic displays of Nazi war crimes — the office created the look of political theater for years to come, a setting that was dramatic but controlled, a scene ready for C-Span. It was the Special Exhibits division of the O.S.S., headed by Eero Saarinen, who would become a pre-eminent postwar architect, that was responsible for honing the concept of the situation room, the stage where the bureaucratic mechanics of war would play out, and which would eventually become such a part of the culture — from “Dr. Strangelove” to the front page of The New York Times — that it would change the perception of how wars themselves are fought.

DESIGN WAS IN some sense the perfect profession to accompany the strange, “soft” side of the war effort, a kind of espionage in itself. In the 1940s, industrial design was, as a 1946 Museum of Modern Art exhibition described it, “a new profession,” suffused with energy, which promised to transform every aspect of daily life: from the spoon you used to stir your coffee to the roads you drove on to the way you communicated, interpreted and consumed ideas. With antecedents in British and European social democracy — the lectures and work of the socialist William Morris, the utopian ideas swirling around the Bauhaus in 1920s Germany positing that design should reflect a society at its most efficient and egalitarian — modern industrial design had a revolutionary mission. Design was art in everyday life. It could have universal applications.