You are quite welcome to visit the sites of the Nature Conservancy or the EDF if you are curious about what they are up to today. I'm not even sure they existed 30 years ago; they certainly are alive and well today. Resources For the Future is another pro-market environmental advocacy group.

As someone who has studied and taught courses at MIT on environmental policy and know something about how its dealt with at universities, if you take environmental policy courses in a Master's program somewhere you'll spend far more time studying the features of different polution credit trading schemes than holding hands while bemoaning the evils of the capitalist system.

Of course, if your definition of "activist" is a freak banging on drums on a street corner, well, yeah, not many of them are looking to corner the market on SO2 futures. But again, we then deal with the trivial -- and the typical.