What is solidarity and why is it, in the words of the historian David Hollinger, “shaping up as the problem of the 21st century”? While all groups that display solidarity have had to contend with who constitutes the “we” and what, if anything, is owed to those who exist outside it, globalization has increased the size of the “we” to species level. In a sense, we are all neighbors, but we are neighbors who do not know each other and with whom we do not share the same language or the same values. What makes this challenge particularly pressing is the awareness that the world’s stability, if not its sheer survival, depends on the creation of new forms of broad-based solidarity.

Amid efforts to come up with alternatives, one place where people have been good at imaging solidarity on a truly global scale is in the wake of real or fictional disasters. What do responses to natural catastrophes, fantastic alien invasions, make-believe zombie apocalypses, and general mass destruction tell us about the kind of solidarity we need today?