October 31st — All Hallows’ Eve — is the day of the launch of “Extinction Rebellion”. Hundreds of us will be descending upon Parliament Square, to declare that we’re no longer willing to stand by while the-powers-that-be frogmarch our species (and most wildlife) towards extinction.

Climate chaos has become an existential threat. And so we’re rebelling.

As if to show that God has no sense of humour, He’s unleashed record-matching floods in Venice to accompany the occasion. Three quarters of the city is underwater. Six people have died in the extreme weather conditions gripping Italy.

This is tragic. And just a tiny taste of the vast tragedies to come, if we don’t act convincingly to match the global emergency we find ourselves in.

Actually, this has precious little to do with God, and everything to do with humanity. Increasingly, “global weirding” means that “natural disasters” aren’t natural at all: they aren’t “acts of God”. They’re caused by us. One of the main three factors behind Venice’s increasing susceptibility to floods is climate-change-caused sea-level-rise. (Another is offshore methane extraction — itself a big contributor to dangerous climate change…)

Venice is a uniquely beautiful place. A wonder of the modern world. I remember with great pleasure attending a conference there. It’s bizarre to see pictures of places one has strolled through now a metre under water.

Venice will succumb. It will become unliveable, and then gradually sink beneath the waves. An early casualty of climate devastation. Like Bangladesh. Like the Maldives.

Unless, just conceivably, we act in ways that are completely outside the box.

In the 1990s, I joined EarthFirst! for “Redwood summer” in California, and we put ourselves on the line to try to stop the clearcutting of those magnificent trees. In the 2000s, I was part of the movement seeking through civil disobedience to disrupt Trident; and I interrupted proceedings in the House of Commons, to protest against the use of cluster bombs in Iraq (I ended up spending an afternoon in the cells at the Palace of Westminster: yes, they have their own tiny prison there). But it’s been years since I engaged in non-violent direct action.

I don't particularly want to be arrested. I don’t want my life disrupted. I’m no wannabe hero.

It’s simply that we cannot wait any longer, while the planet burns. Our own government, in its infinite unwisdom, used the Budget yesterday — just a fortnight after the IPCC’s compelling report on our planetary emergency — to throw £30,000,000,000 at road-building while one five-hundredth of that amount went to tree planting, to “compensate”. Truly shameful, at this moment in history.

So I’m willing to risk arrest.

The idea of the Extinction Rebellion is that, rather than allowing ourselves to be gradually extinguished, we will insist upon the government changing course radically, now. And if they refuse, some of us are ready to go to prison for it.

We may well fail. The odds are stacked against us. The latest blow being the election of a genocidal, ecocidal extremist to the presidency of Brazil.

And we can take little comfort from previous successes. The civil rights movement, or women’s suffrage, or gay marriage: these were liberations for visible groups of oppressed human beings, and didn’t challenge the basic economic system or the exploitation of nature. What we are trying to do instead is to save the future for all of us; and that means changing everything.

Any rational person would bet heavily against us. But to be able to look our kids – or indeed Venetians – in the eye, we need at least to try. Imagine how you’d feel in a decade’s time, once it’s too late – and you hadn’t even tried.

And even if we fail, perhaps we’ll have slowed the juggernaut of destruction down some. Even that would be better than nothing. Much, much better.

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There’s still time. Why not join us? It’s the hour of decision, the eve of destruction, before we become ghosts, our civilisation at best a memory. And who knows? Given the time of year, maybe some of us will even be wearing fun masks…

We’ve little to lose. We’re already losing Venice; and that’s just the canary in the climate coal mine.