Prime Minister Kevin Rudd's first National Security Statement in 2008 identified climate change as a ‘fundamental’ threat to national security. Two years later, Rudd was deposed with little to show for climate activism beyond the largely symbolic ratification of the Kyoto Protocol. Australians largely accepted Rudd's claim that climate change constituted a threat, yet relatively mainstream climate-policy measures were subjected to significant, and ultimately effective, political opposition. This has important implications for climate politics in Australia. This paper, however, focuses on implications for the securitization framework. Specifically, the author argues that this case raises serious questions about the capacity of the framework to account for the mobilising power of security or the dynamics of its construction.