Dumbarton Oaks was the setting for a decisive stretch of postwar atomic-policy deliberations: in March 1946, Oppenheimer and his fellow consultants met there to refine a report proposing international control of atomic energy. The mansion’s Byzantine artworks, towering walls, tapestries, and carefully observed works of art framed discussions about how to keep atomic technology from becoming an instrument of war.

Setting and Meetings

Over ten days in mid-March, the consultants held four all-day meetings at Dumbarton Oaks, a stately mansion in Georgetown. Its walls rose nearly three stories, and magnificent tapestries hung beside a shaft of sunlight that fell on El Greco’s painting The Visitation. An ebony Byzantine cat sat enclosed in glass. These details locate the work of policy not in an impersonal office but in a richly furnished house whose quiet visual order contrasted with the scale of the danger under discussion.

The Report Deliberated There

By early March, the board of consultants had a draft report of about 34,000 words, written by Oppenheimer and reworked by Herbert Marks and David E. Lilienthal. The central problem was that neither a simple international ban nor inspection alone could reliably prevent military diversion: more than 300 inspectors would be needed just to monitor one diffusion plant at Oak Ridge, while inspectors could struggle to detect the diversion of enriched uranium or plutonium from civilian facilities.

The proposal developed through the Dumbarton Oaks deliberations called for an international agency to control and develop atomic energy for civilian purposes, while distributing its benefits as an inducement for countries to participate. Under the plan, the agency would own uranium mines, power plants, and laboratories; nations would give up a limited measure of sovereignty, and no nation would be allowed to build bombs. The mansion thus became the setting for a proposal that treated civilian atomic energy and the capacity to make weapons as inseparable problems.

Reading and Significance

Near the end of the deliberations, Dean Acheson, Oppenheimer, and the other participants took turns reading sections of the draft aloud. Afterward, Acheson removed his reading glasses and praised the document as brilliant and profound. The episode gives Dumbarton Oaks its particular significance in the book: it was not merely a meeting place, but the physical setting where a lengthy technical report was tested in collective discussion and presented as a comprehensive alternative to limited bans or inspection regimes.