In 2007, Kevin Rudd was elected Prime Minister of Australia with the promise of pursuing strong action on global climate change. Less than 3 years later, he was deposed as leader of his party after walking away from proposed climate legislation. One important part of this puzzle concerns the nature of political debate in Australia about climate action, with this debate orienting around the economic costs of climate action. This can be read as a competition between discourses of security: one focused on securing Australia and vulnerable others from the long-term threat posed by climate change, the other on securing Australia and Australians from the short-term threat climate change action posed to continued economic growth. Over time, the latter came to dominate contestation over climate change. This article maps these competing discourses, reflecting on what this case tells us about the politics of climate change in Australia and beyond.