Appeals to solidarity are common in international relations, but solidarity is rarely addressed in International Relations research. In this paper, we theorize the concept, propose a strategy of operationalization and map empirical manifestations in a most likely case: natural disasters. Solidarity refers to mutual moral and material support in times of need. It arises when adversity befalls an innocent victim, prompting expressions of compassion by less affected parties and collective sharing to help the victim recover. Solidarity is neither rare nor a given: we find that in 50 percent of large natural disasters between 1995 and 2018, some form of mutual support occurred. Solidarity emerges most consistently when it is needed most, to address very deadly disasters. Yet, its limited forms – with strong moral support or high material sharing, but not the other – are more common. Our theoretical framework offers insight into the causes and correlates of different solidarity outcomes.
Binetti et al. (Fri,) studied this question.