A week is a long time in politics.

On Wednesday, the chancellor stood up in front of the House of Commons and slashed the tax on domestic flights as part of his Budget.

The head of a climate think-tank described this as the only announcement in the speech that will affect greenhouse gas emissions, and they said, it would increase them.

Despite this, from Sunday Mr Sunak's boss will try and persuade a host of the world's leaders to cut down on their own nation's emissions as the UK hosts the COP26 climate summit in Glasgow. That's not long at all.

Green campaigners criticised the chancellor for the lack of environmental focus coming so close to the UN summit.

Rebecca Newsom, head of politics at Greenpeace UK, said: “The climate emergency should have been the centrepiece of this spending review ahead of the most critical UK-hosted climate talks in years, but Sunak spent more time discussing duty on domestic cider.”

The teetotal chancellor would argue that he introduced an extra tax on long-haul flights, as well as saying that the net zero strategy the government announced last week was investing £30 billion to create the new green industries of the future, and he had championed London as a centre for green finance.

While those things may be true, he missed the chance to major on the environment in one of the set piece political events of the year. Coming so close to COP26, this was surely a missed opportunity to set an example.

Even if the government had fully thrown its shoulder to the wheel, persuading some world leaders would have been a struggle.

Many leaders are not coming the summit and even some of those who will be attending are dragging their feet.

Australia recently pledged to reach net-zero carbon emissions by 2050, but says it plans to do so without ending its fossil fuel sectors. For the world's second biggest exporter of coal, that is quite some feat.

Insulate Britain, as unpopular as the group may be, is attempting to spur governments into acting on the climate crisis.

A video of one, obviously agitated, elderly protestor has circulated online in recent days.

The man had been daubed with blue ink by angry motorists.

Asked about the experience by a reporter he said: "It wasn't painful. It didn't hurt. It was unpleasant, but it's just sad. The whole thing is sad. It's sad that we have to do this."

He went on: "I hate doing it. I'm a retired doctor, I've spent my life trying to help people and I'm reduced to having to do this because the government won't address the problem adequately."

Asked if he was worried about violence being used against him, he said: "Of course, I'm terribly worried."

A week may be a long time in politics, and details fade fast from the memory but images and anecdotes tend to linger - whether it's a note saying there's no money left, Boris Johnson dangling from a zipline while advertising the 2012 Olympics or a teenage girl from Sweden starting a school strike.

Rishi Sunak's inaction in his budget speech may be all but forgotten by the time COP26 rolls around in earnest next week, but the image of a scared old man in a hi-vis vest sat in a road because he's more scared of the climate crisis than angry motorists is likely to linger.

Insulate Britain's methods are questionable, but their cause is not.

The climate is already in crisis and if action is not taken now, things will only get worse.

COP26 offers the best chance to take that action, but the UK's government has not put its best foot forward.

Does sitting in the middle of a junction holding up traffic help persuade anyone? I don't know, but it seems that more still needs to be done.