Optimists maintain that great powers oppose the proliferation of nuclear weapons and have a moral aversion to their use. The Eighth Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) in May 2010 produced a final declaration calling for steps toward complete disarmament. Yet recent optimism belies some contradictory, incremental foreign policy decisions taken by countries like Australia and the United States that could produce a change of meaning for the nuclear nonproliferation norm. Building on the “norm life-cycle” model developed by Martha Finnemore and Kathryn Sikkink, this article links a new constructivist model of normative change to decisions by developed states to expand the global nuclear fuel cycle and provide sensitive nuclear assistance to other countries. An exploratory case study of Australian government policies on nuclear energy and uranium exports (2006-present), including the possible sale of uranium to India, a non-NPT signatory, suggests an important role for elite agency in norm redefinition.