Under Donald Trump, America has not only jettisoned any effort to deal with the climate crisis, but has also attempted to stymie moves by other nations to shift to cleaner forms of energy, such as solar and wind.

The climate crisis is “the greatest con job perpetrated by the world”, Trump told the UN in September, urging other governments to stick to oil and gas (preferably drilled in the US, of course) and ditch the “scam” of renewable energy.

So, the US’s absence from the Cop30 climate summit under way in Belém, Brazil was initially met by other delegates here with a kind of relief akin to when the school bully takes a day off sick.

More on what an absent America means for this year’s climate conference, after today’s climate headlines.

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In focus

Trump’s energy secretary, Chris Wright, said last week that Cop30 is “essentially a hoax” and while there is no US delegation for the first time ever at the annual talks, next year he might show up “just to try to deliver some common sense”.

Not having a recalcitrant US in Belém has allowed the rest of the world to crack on with trying to make up some of the yawning gap between what the science demands to avoid disastrous climate impacts and our lagging response.

The US’s absence is “actually a good thing”, according to Christiana Figueres, former executive secretary of the United Nations framework convention on climate change. “Ciao, bambino,” was her response to the US’s departure from the Paris agreement.

But there are also waves of nervousness rippling through the diplomats here in Brazil. While the world’s leading economic and military superpower isn’t officially present, it is watching. And it could intervene in a similar way to a recent international meeting aimed at curbing shipping emissions, in which US representatives were accused of bullying tactics to derail the process.

Some negotiators have admitted privately to treading carefully, wary of upsetting Trump. Many do not want to say anything publicly about the US, for fear of retribution.

We are still in the early stages of this two-week summit. Should countries start to piece together some momentum towards a strong climate deal here – a deal that requires consensus – Trump could swoop.

“If more concrete decisions come to implement a list of issues, that’s when I expect to start to see pushback diplomatically from the Trump administration,” said Bill Hare, a climate scientist and Cop veteran.

“The negotiators are talking about it and worrying about it. The small countries are all saying, ‘We could be vulnerable. We could get picked off at a capital level.’”

Read more:

• California governor calls Trump ‘an invasive species’ at Cop30 climate talks

• Tussles break out between protesters and security at Cop30 in Brazil

• The temperature at Cop30: Trump’s absence better than a US wrecking ball | Oliver Milman