According to the ACF, policy core beliefs are the glue that holds coalitions together. What happens to coalition structures when policy beliefs change over time? To answer this question, we analyze the Finnish climate change policy subsystem before and after the Paris Agreement. Using panel survey data and methods of social network analysis we find that the coalition structure remains fairly similar, despite the fact that many collaboration ties are severed and new ones are formed. Disagreement between coalitions shifts from fundamental value priorities (economy vs. ecology) to specific policy issues (deforestation, peat as an energy source). The relative stability of coalitions despite belief changes is explained by the fact that newly divisive beliefs are correlated with those that were previously divisive, and by the fact that actors often extend their existing set of collaboration ties based on triadic closure, making the coalition structure path dependent.