This article makes a case for extending social constructivist approaches to the study of grievance in natural resource conflicts. It does this by analyzing the separatist conflict in Aceh, Indonesia, which is often portrayed as a paradigmatic resource conflict due to the importance of the natural gas industry there. It is argued here, however, that natural resource exploitation promoted conflict in Aceh only because it became entangled in wider processes of identity construction and was reinterpreted back to the population by ethnic political entrepreneurs in a way that legitimated violence. Rather than any intrinsic qualities of natural resource extraction, the key factor was the presence of an appropriate identity-based collective action frame. The argument is strengthened by comparison with two other resource-rich Indonesian provinces where resource extraction patterns were similar to Aceh but where no protracted violence occurred because similar identity resources were not available to local actors.