  Social movements rely in large measure on networked communication
technologies to organize and disseminate information relating to the movements'
objectives. In this work we seek to understand how the goals and needs of a
protest movement are reflected in the geographic patterns of its communication
network, and how these patterns differ from those of stable political
communication. To this end, we examine an online communication network
reconstructed from over 600,000 tweets from a thirty-six week period covering
the birth and maturation of the American anticapitalist movement, Occupy Wall
Street. We find that, compared to a network of stable domestic political
communication, the Occupy Wall Street network exhibits higher levels of
locality and a hub and spoke structure, in which the majority of non-local
attention is allocated to high-profile locations such as New York, California,
and Washington D.C. Moreover, we observe that information flows across state
boundaries are more likely to contain framing language and references to the
media, while communication among individuals in the same state is more likely
to reference protest action and specific places and and times. Tying these
results to social movement theory, we propose that these features reflect the
movement's efforts to mobilize resources at the local level and to develop
narrative frames that reinforce collective purpose at the national level.
