There was plastic aplenty at today’s Extinction Rebellion rally in Parliament Square. Plastic shoes, plastic badges, plastic sunglasses, plastic phone covers. A woman offered me a sticker peeled from a strip.

‘Are they plastic?’

‘I don’t know,’ she shrugged. ‘Someone gave them to me.’

XR is starting a week of demos and civil disobedience. I arrived just as a sit-down protest opposite Parliament was being cleared by police liaison officers. ‘If you occupy the road you’ll be arrested under Section 14 of the Public Order Act, 1986,’ they said politely.

An XR steward went around quietly advising the tarmac-squatters: ‘Don’t acknowledge what they’ve said. Then they can’t say you knew you’d broken the law.’

But the cops won that one. An hour later the street was clear.

Dozens of rebels were waving tree-saplings in full leaf. They were from beeches, I was told.

‘Did you rip that off the tree yourself,’ I asked one protestor.

‘No. I was given it.’

A neat cut at the thick-end of the branch suggested that a tool had been used. Someone told me the branches had been specially harvested at a farm in Kent.

The mood was festive and relaxed, despite the constant screech of whistles and drums. Families let their children caper around in the sunshine. Helpful rebels handed out sun-block. Groups of meditators sat on the grass in the lotus position and slowed their breathing. Above them fluttered an Earth Vigil banner. ‘United in love and grief for our SACRED EARTH’. It was a great day for home-made placards. Most of them seemed to have been written by angry depressives.

‘Fuck Business As Usual.’ ‘Delay = Death.’

A lot of the placards sounded like excerpts from domestic tiffs.

‘If I give a crap, why can’t you?’ ‘It’s not a crime to understand science.’ ‘I’ll be less rebellious when you take more notice of the FACTS’.

An Asian cook was doling out free rice and beans from a cart blazoned with a rare message of hope. ‘Chant Hare Krishna and be happy.’ He didn’t seem to mind that his signature dish was being dive-bombed by confused late-summer wasps.

The speeches began. Robin Boardman, nattily dressed in a grey suit and a pink tie, formally opened the protest and gave the crowd this estimate of humanity. ‘We are a sick mass-extinction event.’

Perhaps he’s more fun at parties. He repeated his undemocratic demand for a new National Assembly to ram through XR’s agenda. And he made no attempt to conceal his instincts. ‘We declare the bonds of the social contract null and void.’

He urged everyone to join the campaign because it is now ‘a sacred duty to rebel against the government.’ He promised to ‘act with ferocious love on behalf of life.’

‘Ferocious love’ sounds chilling.

He was followed by a poet who quoted Gandhi. Then came a star speaker from XR’s international division, Esther Stanford-Xosei. She labelled society ‘a toxic system of death’ and condemned ‘the so-called mother of parliaments’ as ‘a crime scene.’

It got more troubling. She said that she was a ‘survivor of genocide’ and she argued that the ultimate goal of colonialism had been the extermination of all dark-skinned races. ‘We were never meant to be here,’ she said.

Virtually every member the crowd was white but they seemed content to learn that they were descended from genocidal maniacs. Many cheered and waved their severed branches.

Stanford-Xosei’s indignation began to play havoc with her grammar. ‘We are still being genocided today.’

Then she reached the gist of her argument. Cash. Reparations must be paid, she said, for the crimes of history. By this stage, she had wandered some distance from the topic of climate change and she articulated her hopes for ‘a pan-African super-state.’ She didn’t say what its policy on renewables or single-use plastic might be. Perhaps that’s for a later speech.

After the oratory, it was time for fun. A musician with no surname was announced. ‘Leon! A multi-instrumentalist from south London.’

Leon had left all his instruments at home, along with his surname, so he had to make do with a funk-soul dance-track. ‘Break all the rules,’ he sang, jiving on stage and encouraging the crowd to copy him.

The XR rebels mooched obediently across the square. Everybody danced. But no one had rhythm.