The protest wave following the Fukushima nuclear accident in 2011 both vitalized the environmental movement in Japan and created tensions within it. This chapter looks at the relation between anti-nuke protesters and established environmental organizations. Using text analysis and interviews with major anti-nuke protest groups and environmental organizations, I trace how tensions built up and evolved between these two strands of activism in the years 2011–2014. These tensions in part revolved around whether to prioritize nukes or the climate, but also reflected differential positions in regard to political power. I argue that changes in the discourse of the environmental organizations are a measure of the impact of the anti-nuke protests and a testimony to the ability of anti-nuke protesters to, at least in part and for a while, send tremors through the existing system of green governmentality. The chapter contributes to an understanding of Japan’s social movement scene as a whole by highlighting the pivotal role of post-Fukushima protest in repoliticizing the political landscape, normalizing protest and creating a populist form for protests that could subsequently be adopted by other protests movements that have sprung up in Japan.