Energy security studies have expanded from their classic beginnings following the 1970s oil crises to encompass various energy sectors and increasingly diverse issues. This viewpoint contributes to the re-examination of the meaning of energy security that has accompanied this expansion. Our starting point is that energy security is an instance of security in general and thus any concept of it should address three questions: “Security for whom?”, “Security for which values?” and “Security from what threats?” We examine an influential approach – the ‘four As of energy security’ (availability, accessibility, affordability, and acceptability) and related literature of energy security – to show it does not address these questions. We subsequentl...