Free Arctic 30 image via brightblightcafe/flickr. Creative Commons 2.0 license.

One evening in October 2013, the Russian-born climate change activist Dima Litvinov perched himself on the edge of his bunk in cell 423 at Murmansk SIZO-1 isolation jail in the Arctic Circle, and wrote a letter to his friends on the outside.

A month earlier he and 27 campaigners – and two journalists – were arrested when their Greenpeace ship was seized by President Vladimir Putin’s commandos after a protest at an oil platform operated by Russia’s state-owned energy giant, Gazprom. The ‘Arctic 30’, as they became known, were charged with piracy, and Dima now faced 15 years in prison.

‘I can only speak for myself, since I am isolated from my comrades,’ he wrote.

‘But from my perspective, if our action and the follow-up we are living through will lead to the undermining of the Arctic oil companies, and to get people all around the world, and especially in Russia, to understand the reality and urgency of the crisis we are attempting to avert – well that’s well worth a few weeks or months or (sigh) even years behind bars. I am hoping that I can count on you, my friends and colleagues, to continue the campaign while the 30 of us are “enjoying” this forced vacation.’

Dima would readily admit that there were moments during his ordeal when he was scared. Indeed, most of the 30 say they often endured a dark night of the soul as they contemplated losing their best years to Putin’s judicial machine.

But even behind bars, they all demonstrated a remarkable commitment to the cause that brought them to the Arctic in the first place – a determination to put their bodies in the way of the fossil fuel behemoths whose rigs can only drill in Arctic waters because rising temperatures are melting the polar ice. The Arctic 30 knew that climate change is the biggest story in the world, and it was one that was not being told.

The youngest of the 30 was Camila Speziale, a 21-year-old Argentinian climber who was on her first extended trip abroad. Held in solitary confinement, her only contact with her friends in jail came through coded taps on a radiator pipe and shouts over the wall during gulyat – the hour each day in which the prisoners were locked in a dark box to exercise.

Camila could have been forgiven for questioning her commitment to climate change activism. Instead, the other prisoners remember her shouting out, ‘Everybody, we did the right thing. And if we did the right thing, then what can go wrong?’

It is worth reflecting on that passion and commitment as we survey the political scene in Britain. We are currently in the midst of a general election in which kitchens have commanded more attention than the climate.

In the leaders’ debates only the Green Party’s Natalie Bennett deigned to mention the breakdown of the biosphere, while the Conservatives’ huskie-era green logo – a once-mighty oak – has morphed into a union jack-coloured wink at UKIP voters.

When the tabloids published their inevitable feature articles on ‘The Green Party’s most bonkers policies’, they included the commitment to phase out coal-fired power stations, as if the recommendation of mainstream opinion in the scientific community is of a piece with homeopathy and astrology.

Meanwhile, a Shell oil rig is right now crossing the Pacific Ocean on its way to Arctic waters, where the world’s second-biggest oil company intends to follow Gazprom and drill in the melting north. Shell first tried to crack the Arctic in 2012, but the company was forced to retreat after one of its rigs caught fire and another ran aground in heavy seas.

US President Obama is set to give the green light to Shell’s latest venture, despite its woeful track record. The same President consented to deepwater drilling in the Gulf of Mexico, in the face of credible warnings that a blow-out would be catastrophic.

Exactly five years ago, on 20 April, the Deepwater Horizon platform exploded with the loss of 11 lives. By the time the leak was plugged, 5 million barrels of oil had been spilled.

A similar accident in the Arctic could be almost impossible to clean up. The returning winter ice would force the rescue team to retreat, while spilled oil would gather under the ice and be carried thousands of kilometres by polar currents.

And even if there are no spills (unlikely), Shell will still be exploiting the melting ice to drill for the oil that caused the ice to melt in the first place.

Now that is bonkers.

Dima was not the first member of his family to be jailed in Russia for his political beliefs. His great-grandfather was imprisoned by the Tsar, his grandfather by Stalin.

His father is Pavel Litvinov, the famed dissident who watched Russian tanks rolling into Prague in 1968 and resolved to act, in the certain knowledge that he would face the full fury of the Kremlin.

Days after the Prague Spring, Pavel and 7 of his friends sat down in the Red Square and unfurled banners. ‘Shame to the occupiers! For your freedom and for ours! Long live free and independent Czechoslovakia!’

In his Pulitzer Prize-winning account of the fall of the Soviet Union, the New Yorker editor David Remnick describes Pavel’s protest as ‘one of the first blows against the regime’. He was sentenced to exile in Siberia, where Dima grew up.

In 1968, it was hard to imagine that the Soviet Empire would, in just two decades, crumble in the face of street protests. We have a similar period of time in which to affect what sometimes feels like an equally improbable revolution against fossil fuels.

By the 2030s, our electricity must be largely generated without releasing carbon, or the target of limiting global temperature rises to two degrees will be missed. If decarbonization is to happen, then we will need many millions to join the movement.

We can’t all demonstrate the commitment exhibited by Dima, Camila and the other Arctic 30 prisoners. But this movement must grow strong enough to cut through the denial manifested in the election campaign and in Shell’s imminent Arctic drilling programme. Only then will we keep it in the ground.

After his son was released in the face of global protests, I asked Pavel Litvinov how he thought his stand against the Soviet regime compared to Dima’s action against Arctic oil drilling and climate change.

‘The protests are different, of course,’ Pavel replied, ‘but in a way the challenge that Dima and I both had in front of us was similar. We both wanted to speak up for somebody who was attacked by a large totalitarian government. In my case we spoke in defence of a small country, Czechoslovakia, which was suddenly oppressed by its big neighbour.’

‘And in the case of Dima he was speaking for the Arctic, which also didn’t have its own defence, and to some degree the defence of the Arctic is a metaphor for the defence of humans and human rights. It is our life, because if the Arctic cannot survive then neither can we. It is our canary in the coal mine. If life is unbearable there, then it will become unbearable to us. So there was a similarity. You try to raise a voice because you have nothing but your voice. A voice to speak up for something which cannot speak up for itself.’

Ben Stewart was a leading figure in the campaign to free the Arctic 30, and his book about their ordeal, Don’t trust, don’t fear, don’t beg, is available now.

Join the crew of the Rainbow Warrior for a unique insight into the personal stories behind Greenpeace actions and campaigns, including the Arctic 30, in Rainbow Warriors, by Maite Mompo, available from the New Internationalist online shop.