There is a good chance that one day, years down the road, someone will ask what you did about climate change. It could be your kid, your grandkids, maybe someone you don’t know, maybe a whole generation. It will be one of those moments when you’ll want to be standing on the right side of history. Never before has there been one singular, terrifying threat that eclipses all of the social justice and environmental struggles that have come before. The current Californian drought and deadly Indian heatwave give us an idea of where we’re headed, but it will get worse. Researchers proved that a severe drought heavily contributed to onset of the civil war in Syria – we’re looking into a future of war, hyper-militarised borders, unstable and disastrous weather patterns, food shortages and risky geo-engineering schemes.

And yet, as author, activist and global intellectual Naomi Klein says in her new book This Changes Everything, climate change is also an opportunity. It’s a chance to unify all of those diverse global struggles – battles against austerity, racism, fracking, drilling for oil in the Arctic, and much, much more – that are being fought in courts and governments, on the streets, the high seas, and online. “The environmental crisis isn’t separate from political and economic crises,” she points out, “it supercharges each one of them with existential urgency.”

After all, as Klein says, we’re all fighting the same enemy – rampant, unchecked neo-liberalism – and it’s only in joining forces to form a social movement that spans every major issue on the left and in the environmental sphere, that we have our chance to finally get it right. This Changes Everything is as much as a call to arms, as it is a description of “Blockadia”, interconnected pockets of global resistance where activists are fighting the fossil fuel industry in roving, international conflict zones.

But perhaps even more importantly, in her book Klein has created a carefully researched blueprint that details how we can transition to a new low carbon economy in the next 15 years. “Climate change gives us a reason to create a new economy, to transfer public investment, reclaim the commons, create a regulatory tax system that’s fair and create millions of jobs,” she told an audience at a Guardian Live event in London. “The only way to win is to build a movement with a huge amount to gain.”

“It’s pretty precarious, this idea that we have insulated ourselves from the natural world just because we live in cities” – Naomi Klein

Klein’s argument – that the left and the environmental movement should join forces, is a new one in mainstream politics – but it makes so much sense that you have to wonder why it took this long. What marks out This Changes Everything from the multitude of ominous books about global warming, is that it offers hope. “Climate is the big tent we’ve been waiting for,” she says, “and why wouldn’t it be? We’re all under the Earth’s atmosphere, we need to start acting like it.”

Do the activists who make up Blockadia feel part of this larger movement against climate change, or it more about their individual struggle?

Naomi Klein: I think it’s both, that is what’s exciting about this moment. It definitely starts with the local concerns – that’s the impetus. With this huge climate march in New York, all of these pieces of the resistance – local movements that are fighting fracking, mountaintop removal, coal mining and tar sands pipelines, oil trains and refineries in their backyards, people who are getting their schools to divest from fossil fuels – they were all there. The old division between the local and the global is broken down and that definitely wasn’t always the case. That’s changed.

You’ve said that traditionally, the fossil fuel and chemical industry would exploit land near the most marginalised, vulnerable communities – you call them “sacrifice zones” – what role are these communities playing in Blockadia?

Naomi Klein: With tar sands, it is heartening the extent to which indigenous voices from Northern Alberta, who are the most directly impacted, now have an international platform. They were at the very front of the climate march. In the film that my husband is making to go with the book, one of the things that is really exciting is that some of the most prominent leaders are young women in their 30s. In the film you meet these women and see where and how they live, and the stakes of this fight for them. I think they deserve more of a platform and to be recognized as climate leaders.

Are young women leading the climate change movement in other parts of the world too?

Naomi Klein: Yes, in a lot of the movements that I follow, younger women are playing a really dominant role. I’m seeing more leadership from young women than I have seen in past movements. It’s a deeper form of leadership too, because it’s more rooted in specific places.

This movement in Greece against a gold mine that I speak about in the book – it’s young mothers, women in their 30s with young kids. Three women wrote this extraordinary open letter addressed to the women of the world. There is something about that sense of responsibility, the care for the land, for their kids, that is driving a lot of this. But it’s also love of place, and it’s not just a women’s issue by any means.

A lot of people have told me they think the most powerful quote in the book is from Alexis Bonogofsky from Montana. Speaking about this part of Montana that is in the bull’s-eye of new coal mines and new coal railways, she says, “Love will save this place” and it’s so beautiful. She’s just such a powerful person – she’s a rancher, a fourth generation Montanan.