Why does Larry Niven hate environmentalists?

Recently I read his book "Fallen Angels"; the backstory involves the Green Party being elected, banning all advanced technology, and bringing on an ice age.
He has also apparently written "Lucifer's Hammer", where the main characters are in a nuclear plant being attacked by savage environmentalists who are cannibals are something.

So is he just an enormous troll or did a book about global warming kill his mother?

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Niven sucks. Seinfeld sucks. Niven's purportingly (and cringingly not) biographical series sucks. I think he is a Jew, cause he's always bleeting on about the holocaust, and most probably views himself as some sort of patriarchal media producer for the stupid plebs. He will also be rich and content with his life, although ultimately not anywhere near the top of the human food chain. Oh, sorry, I am writing about Larry David.  Well, now you'll know to avoid him, anyway. Peace out.