The basic technologies that underlie nuclear power were first developed during the Second World War by the United States for purely military purposes. Since then, extensive civilian research and the use of nuclear technologies for peaceful ends has not erased this military heritage. Almost all nuclear technology in use around the world today is ‘dual use’, able to contribute to the production of fuel for nuclear reactors or the explosive components of nuclear weapons. For this reason, there is serious concern that supposedly peaceful nuclear programmes are being used for, or could become, cover for the development of nuclear weapons.