In his panorama of Mexican popular collective action between 1968 and the 1990s, Sergio Tamayo shows how one national campaign shaped the next. The transformation of popular contention, he concludes,

was a cumulative process of citizens’ actions that during the first five years of the 1990s reached a level of extensive participation, using every sort of resource, as much legal and formal as informal and violent … As for Mexico City, the citizenry appeared with great strength, certainly a result of the city’s special character as capital of the republic and urban center where regardless of its origin the national political debate concentrated.

(Tamayo 1999: 353)