Recently, records have been published from the internal discussions in the Carter administration (1977–80) on the feasibility of convincing Japan to halt its plutonium-separation program as the United States was in the process of doing domestically. Japan was deeply committed to its program, however, and President Carter was not willing to escalate to a point where the alliance relationship could be threatened. Forty years later, the economic, environmental, and nonproliferation arguments against Japan’s program have only been strengthened while Japan’s concern about being dependent on imports of uranium appears vastly overblown. Nevertheless, Japan’s example, as the only non-weapon state that still separates plutonium, continues to legitimize the launch of similar programs in other countries, some of which may be interested in obtaining a nuclear weapon option. Read this free-access article in the September/October issue of the digital Journal.