Economics, demography and social media only partly explain the protests roiling so many countries today

IT IS HARD to keep up with the protest movements under way around the world. Large anti-government demonstrations, some peaceful, some not, have in recent weeks clogged roads on every continent: Algeria, Bolivia, Britain, Catalonia, Chile, Ecuador, France, Guinea, Haiti, Honduras, Hong Kong, Iraq, Kazakhstan, Lebanon, Pakistan and beyond.

Not since a wave of “people power” movements swept Asian and east European countries in the late 1980s and early 1990s has the world experienced such a simultaneous outpouring of popular anger. Before that, only the global unrest of the late 1960s was similar in scope.