  Observations of long rang azimuthal correlations in small collision systems
(p+p/A) have triggered an enormous excitement in the heavy-ion community.
However, it is presently unclear to what extent the experimentally observed
correlations should be attributed to initial state momentum correlations and/or
the final state response to the initial state geometry. We discuss how a
consistent theoretical description of the non-equilibrium dynamics is important
to address both effects within a unified framework and present first results
from weakly coupled non-equilibrium simulations in \cite{Greif:2017bnr} to
quantify the relative importance of initial state and final state effects based
on theoretical calculations.
