InfoBrazil has published an article raising questions about whether Brazil might be developing some sort of nuclear weapon, based on its refusal to let the IAEA look at the centrifuges used to enrich uranium in Brazil. This is a touchy issue, because it is Iran’s centrifuge program that has created the most controversial problems for its nuclear program.
One important difference is that Brazil probably does not pose a nuclear threat to anyone, even if it develops nuclear weapons, unlike Iran, which poses a threat to Israel, Iraq, and perhaps a few other neighbors. In the old days, when I served in Brazil dealing with the nuclear issue in the American embassy there, Argentina was a nuclear rival with Brazil. Argentina took the lead in defusing this rivalry. Nevertheless, if Brazil developed a bomb, Argentina might feel pressed to develop one, too.
Another important difference is the way safeguards imposed by the IAEA are handled in Brazil and Iran. It appears that Brazil has been much more forthcoming with the IAEA, only imposing the restriction that IAEA inspectors cannot look at the centrifuges. The IAEA can monitor what goes into and comes out of the centrifuges, thus assuring that no uranium is being “highly” enriched. Iran, on the other hand, has been much less cooperative, and the IAEA has had to be much more insistent to find out where the centrifuges are, and then to find out what they are doing.