Unity or Estrangement Under Crises? Perceived Resource Scarcity Moderates the Effect of a Common Threat on Intergroup Cooperation

Human history and recent empirical studies have documented many cases of human unity or estrangement during global crises. This reflects that a common threat may not always promote intergroup cooperation. An intriguing question arises: What determines the effect of a common threat on intergroup cooperation? In response, we proposed and tested the moderating role of perceived resource scarcity in the effect of a common threat on intergroup cooperation. We found that when perceived resource scarcity was low, common threats posed by pandemics (Studies 1 and 2) and earthquakes (Study 3) promoted intergroup cooperation in controlling outbreaks, building public medical systems, and reducing public resource depletion. However, the effect attenuated when perceived resource scarcity was high. The findings broaden our understanding of common threats and provide avenues to enhance intergroup cooperation in the face of interminable global crises.