Yes, I think the reason Marxism succeeded was because of those elements. You almost have a complete set - bad evil people on one side, heroic missionaries on the other, and the promise of an inevitable paradise.

As for doctrine - people appear to, but only as cover. Historically, many doctrinal disputes have really been about tribal status and loyalties. It's always fun to read history from the middle ages and Renaissance where furious supposedly-religious debates - like the one about the date of Easter which killed off Celtic Christianity in Britain - are clearly all about who is top dog.

The Marxists did a lot of the same thing, of course. Doctrinal struggles were really either individual or tribal power struggles.

The point isn't the details of the doctrine, but the social dynamics, and especially who's considered inside and in charge and who's considered out. They're about tribal markers, not disinterested intellectual curiosity.

afew:

And I see the difficulty for us in precisely that element: what progressive teleology?

The key point. We don't. Or at least, we don't have a positive one - only a negative one which says that if people don't behave, the Earth will spank them and send them to bed without supper.

We don't need to start a cult. But I think we do need to work out a way to start promising people paradise.

It has to be a realistic-ish paradise, for the sake of our own integrity. But framing debates about sustainability as a movement towards a paradise that can be gained rather than as something negative to be avoided is going to make a huge difference to the cultural stickiness of the practical measures that are going to be needed.

The right already has this. Capitalism implicitly promises a trickle-down paradise of perfect individual freedom of choice and infinitely expandable living standards.

The far right uses a similar frame for immigration, suggesting that if it weren't for [these outsiders] paradise would be possible.

So progressives need to start using similar frames. A tougher trick would be to sell the new frame back to the right, co-opting their memes and replacing them with this progressive teleology.

I'm not sure how you'd do that, but it's beginning to look more and more like a necessity if big changes are going to happen with a minimum of friction.