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.
Not really; but talking about it more also seems like it will have approximately zero marginal benefit, and trying to insinuate that other people are immoral is probably net counterproductive.