Peoples' movements and protests
The world market system is based on far-reaching division of labor. This means that people live under increasingly different conditions. In medieval Europe, people were either farmers or craftsmen. Therefore, there were largely peasant movements and artisan movements. On the other hand, these were of course strongly geographically limited. In today's global world, there are all sorts of identities and communities from which to build popular movements, at the same time as the movements have a tendency to get a global reach.
But on various occasions, attempts have been made to create links between different identities and / or different kinds of collectives, in order to reach greater breadth and create greater ability to strike against state, capitalist or other upper-class power. Sometimes such attempts have emerged spontaneously, sometimes they have been tightly consciously controlled.
And sometimes such cross-organizations have achieved very great results.