Since I don't live in the USA, I don't have a feeling for the current political climate [pun intended] there, so take the following remark with a grain of salt.

But if I go by my gut feeling, I'd say that there is a difference between wanting to understand by what and how much the climate is influenced by various factors (as unpolitical as possible in this academic discipline) vs having a political stance which policy measures to take based on these insights (e.g.

- do nothing and tolerate the possible risks

- lobby for strongly reducing CO2 emissions

- lobby for doing geoengineering to stop the climate change

). My feeling is that at least some climate scientists want to be both researchers and "politicians" for their academic discipline.