People who dismiss fiction because they don’t know “what it’s good for” or argue that “it doesn’t accomplish anything” (I know a few such folks) might want to take a look at Robert Macfarlane‘s essay in the Guardian on Edward Abbey’s 1975 novel, The Monkey Wrench Gang. Macfarlane points out that the book, which follows a tribe of activists taking their revenge on those who’ve abused the land in the southwest desert, not only influenced a generation of environmental activists (Earth First! in particular), but was intended to do so:
Every now and then, the imaginary forms of literature feed back into the lived world with startling consequence. They assume real-world agency in ways that exceed the cliché of “life imitating art”. Abbey’s novel triggered one of these unusual feedback events. “This book, though fictional in form,” he wrote in an enigmatic epigraph, “is based strictly on historical fact. Everything in it is real or actually happened. And it all began just one year from today.”
From there, Macfarlane largely muses on why Britain doesn’t have an environmental literature to call its own, but also suggests that the theme has endured in American literature. If it has, I’m not sure Macfarlane’s examples prove his point; the only example he provides from the last two decades is Cormac McCarthy’s The Road, which he writes has a “vast and as yet unmapped influence.” (How do you know it’s vast if it’s unmapped?) I think of The Road more as an apocalyptic novel than an environmental novel; the two overlap, but the former has been around since the Cold War (or the Bible, if you feel like being cute about it), while books like Abbey’s were very 70s products.
To the extent I can think of examples, novels about the environment and environmentalists aren’t the deliberate calls to arms that The Monkey Wrench Gang was. Back-to-the-landers certainly don’t come off as especially admirable in T.C. Boyle’s Drop City, and the slow environmental wreckage noted in Richard Powers’ The Echo Maker registers as an inevitability, not something to be agitated against. It may be more that Abbey’s book was more of its particular moment than of any long-running American tradition that continues today. And the book’s brand of environmentalism has been corrupted in the years since, novelist Joy Williams suggests in her 2001 essay collection, Ill Nature:
Joyce Carol Oates suggests that the reason writers—real writers, one assumes—don’t write about Nature is that it lacks a sense of humor and registers no irony. It just doesn’t seem to be of the times—these slick, sleek, knowing, objective, indulgent times. And the word environment. Such a bloodless word. A flat-footed word with a shrunken heart. A word increasingly disengaged from its association with the natural world. Urban planners, industrialists, economists, developers use it. It’s a lost word, really. A cold word, mechanistic, suited strangely to the coldness generally felt toward Nature. It’s their word now. You don’t mind giving it up.
markathitakis.com 
The only example that comes readilly to mind is The only example that comes readily to mind is Ken Kesey’s Sailor Song. It is certainly the least of Ken Kesey’s books by a long shot. The only other example that I can think of at the moment is another Kesey book: Sometimes a Great Notion, which is a far superior work, and one that takes (ironically) a less than critical view of the logging industry.
Well, *I* get the Eno allusion.
I write this as a professional organizer, a full-time environmentalist and a lifelong crusader: the question should be rejected. I’m with Eudora Welty on this one. The novelist must not crusade.
As someone who works in the political/activist world, the folks in that world are literalist, humorless people by and large. They are not imaginative folks. They have trouble getting something that is not a precise call to action, that doesn’t clearly relate to an understandable “cause.”
Those of us who love literature understand that is a virtue in and of itself. It’s that inherent value that we should pursue and if there are folks who just don’t get it, who think books are no good if they don’t advocate or regale, these are folks who don’t get that those books would be empty. That the purpose of books is to connect, and to do it in that middle/grey ground in which we all can actually really identify.
Grey has no place in a campaign. It’s all a book should be about.
So, reject the question. Stay the course.