A society that takes progress as its religion does not look kindly on despair. If you are expected to believe everything will keep getting better, it can be difficult to admit to believing otherwise. This is doubly true for political activists. If you've devoted your life to fighting for a cause, you will probably feel duty bound to continue supporting it, at least in public, however hopeless it may begin to look.

Hope is certainly in short supply in environmental circles these days. With the failure of yet another global summit to "protect the planet" – this time the Rio+20 Earth summit – a tipping point seems to have been reached. Green activism has achieved a lot in five decades, but it has been unable to prevent the global industrial machine from continuing to destroy wild nature and replace it with human culture. There is no prospect of this changing in the near future, and we are reaching the point now when many prominent greens, having denied this reality for so long, are beginning to admit this in public.

So: what next? One increasingly fashionable answer is offered by a coalescing group which we might call "neo-environmentalists". The resemblance between this group and the neoliberals of the early 70s is intriguing. Like the neoliberals, the neo-environmentalists are attempting to break through the lines of an old orthodoxy which is visibly exhausted and confused. Like the neoliberals, they speak the language of money and power. Like the neoliberals, they cluster around a few key thinktanks: then, the Institute of Economic Affairs, the Cato Institute and the Adam Smith Institute; now, the Breakthrough Institute, the Long Now Foundation and the Copenhagen Consensus. Like the neoliberals, they think they have radical solutions.

Neo-environmentalism is a progressive, business-friendly, postmodern take on the environmental dilemma. It dismisses traditional green thinking, with its emphasis on limits and transforming societal values, as naive. New technologies, global capitalism and western-style development are not the problem but the solution. The future lies in enthusiastically embracing biotechnology, synthetic biology, nuclear power, nanotechnology, geo-engineering and anything else new and complex that annoys Greenpeace.

According to the neogreens, growth has no limits. We are, in the words of their spiritual leader, Stewart Brand, "as gods", and must accept our responsibility to manage the planet rationally through powerful technologies guided by science. Wilderness does not exist, "nature" is a human construct, and everything that matters can be measured by science and priced by markets.. Only "romantics" think otherwise.

Neo-environmentalism is beginning to make waves in certain circles. Brand gives talks all over the world arguing the case for megacities and GM crops; British writer Mark Lynas gets airtime to promote nuclear power and attack his former green friends as "Luddites"; US writer Emma Marris argues in her book Rambunctious Garden that there is no real wilderness left to protect; scientist Peter Kareiva, who works for the world's biggest conservation group, the Nature Conservancy, argues that conservation should aim to protect wild nature not for its own sake, but if and because it benefits humans. The Earth, say the neogreens, belongs to homo sapiens now. The value of nature is measured by what we can do with it.

Some of this may shock old guard greens – which is the point – but it is not a new message. It is simply the latest variant on the old Wellsian techno-optimism which has been promising us paradise for over a century. The neo-environmentalists are growing in numbers at present not because their ideas are new, but because they offer a business-friendly worldview which, unlike the tiresome old green message, is designed to make people feel comfortable about their plane flights and their iPads. Science and business will provide. Nature will adapt. Optimism is permitted again. Indeed, it is almost mandatory.

But maybe the green movement was asking for it. For some time, mainstream environmentalism has demonstrated a single-minded obsession with climate change and technological solutions to it, to the exclusion of other concerns. Its language and its focus have grown increasingly technocratic and scientistic. I would guess that most people have a love of nature in some form; but few of them love arguing about whether nuclear power is better than gas. Any campaign to protect the wild world which avoids acknowledging our intuitive, emotional relationship with it will leave itself open to the kind of heartless ideological assault it is now receiving from the neogreens.

Global campaigning for an abstract "environment" does not appear to work. What does work is engaging with nature on a human scale. Perhaps the best rejoinder to those who believe the world is a giant spreadsheet is an engagement with its messy, everyday complexity. A kind of vernacular environmentalism; an engagement not with "the environment", but with environments as we experience them in lived reality. Perhaps it's time to go back to basics.

So we might learn what grows wild in our local area and whether we can eat it. We might build up a bank of practical skills, from horticulture to land management. We might go out at night and plant seeds in vacant flowerbeds near where we live. We might work on small-scale engineering projects, from water purification technologies to micro-solar panels. We might work to save bees or butterflies or water meadows or woodlands or playing fields that we know and have a relationship with. We might walk in the hills, or on the canal bank, or in the local waste ground; get to know our place and how it works.

I can hear the rejoinder already: "None of this is going to save the world!" It's true. But we've had four decades of trying to "save the world", and we have failed utterly. This would be a good time to step back, to get our hands dirty and our feet wet, to smell the rain when it comes and get a feel for where we are on this Earth and what, at the root of it all, we can still usefully do.

"All great civilisations," wrote the Irish poet Patrick Kavanagh, "are built on parochialism." If the alternative is trying to act like gods, then I'm with the poets.