  Human behavior often exhibit a scheme in which individuals adopt indifferent,
neutral, or radical positions on a given topic. The mechanisms leading to
community formation are strongly related with social pressure and the topology
of the contact network. Here, we discuss an approach to model social behavior
which accounts for the protection by alike peers proportional to their relative
abundance in the closest neighborhood. We explore the ensuing non-linear
dynamics emphasizing the role of the specific structure of the social network,
modeled by scale-free graphs. We find that both coexistence of opinions and
consensus on the default position are possible stationary states of the model.
In particular, we show how these states critically depend on the heterogeneity
of the social network and the specific distribution of external control
elements.
