This lengthy report was State Department Bureau of Intelligence and Research's contribution to the first National Intelligence Estimate on the nuclear proliferation, NIE 100-6-57. Written at a time when the United States, the Soviet Union, and the United Kingdom were the only nuclear weapons states, the “Fourth Country” problem referred to the probability that some unspecified country, whether France or China, was likely to be the next nuclear weapons state. Enclosed with letter from Helmut Sonnenfeldt, Division of Research for USSR and Western Europe, to Roger Mateson, 4 June 1957, Secret

Brazilian nationalism has often posed a challenge to US official precepts on the way the world should work and these estimates convey the deep Brasilia-Washington gap over nuclear policy during the 1980s. The SNIEs from 1983 and the 1985 update emphasize Brazil’s quest for technological-industrial autonomy which in nuclear terms meant developing an indigenous program to master the fuel cycle, including uranium enrichment and plutonium reprocessing capabilities. In seeking those objectives, Brazil did not want to face any constraints, and its leaders were unresponsive to U.S. or other pressures for safeguards on nuclear facilities.

The US Embassy in Brazil quotes a Brazilian ministry official who declares Brazil will continue its nuclear program “despite all the threats and reprisals” from the US. The unnamed official goes on to say, “The Americans, our allies, are behaving in a way worse than that of our common enemies, the Russians.”