A rapid and widespread institutionalization of climate security is underway, led by powerful states and international organizations. Recognition of the climate crisis by security actors as a serious threat to humanity is long overdue, but it is imperative that this institutionalization is critically scrutinized. This commentary highlights specific dangers that accompany the institutional mainstreaming of climate security, including a non-reflexive integration into traditional security paradigms, a growing geopolitical separation between discourses emerging from the Global South and North, and policymaking that tends to draw from a narrow view of the science. Science-based and actionable research informed by pluralistic understandings of climate security is needed to counter this trend.