In the US 8 out of the top 10 environmental organizations with most membership oppose nuclear power broadly and the majority oppose wind and solar locally so I think we can safely conclude that climate change is not important to US environmental causes.
The primary work by US environmentalists (or at least the popular ones) is in ensuring rich people’s homes abut publicly-maintained parks.
What are you using as the "top 10 environmental organizations" and which of them oppose wind/solar?