  Proof-of-Stake (PoS) blockchain systems, especially those that allow
stakeholders to organize themselves in ``stake-pools'', have emerged as a
compelling paradigm for the deployment of large scale distributed ledgers. A
stake-pool operates a node that engages in the PoS protocol and potentially
represents a large number of smaller stakeholders. While such pooled PoS
operation is attractive from various angles, it also exhibits a significant
shortcoming that, so far and to the best of our knowledge, has not been
sufficiently understood or investigated. Pooled PoS operation, to be effective
and not lead to sub-optimal dictatorial or cartel-like configurations, should
enable the stakeholders to revoke and re-delegate their stake in a way that is
aligned with their incentives. However, given that stake-pool operators are
exactly those entities who determine what transactions are to be recorded in
the ledger, they are quite likely to form a cartel and censor any transaction
they want, such as those that attempt to adjust the current stake-pool lineup.
In this way, a power grab takes place, where the stake-pool cartel perpetuates
its control over the PoS system. We first model and observe formally the
emergence of the above problem in pooled PoS systems, and then we describe an
anti-censorship mechanism that takes advantage of the underlying cryptographic
functions of the ledger and the nature of peer-to-peer networks to diffuse
information without suppression. We provide a thorough game-theoretic analysis
of this mechanism discovering various types of Nash equilibria which
demonstrate that the ``revolution'', i.e., the strategic decision of pool
members to withdraw support from a censoring cartel as well as the pool
operators to step down, can be incentivized, under suitable and plausible
conditions in the utility functions of the involved participants.
