At the 2025 United Nations General Assembly in New York, President Donald Trump once again thrust climate change into the international spotlight—though not in the way many had hoped. In a speech that ran for more than ten minutes, Trump labeled climate change "the greatest con job ever perpetrated on the world," dismissed carbon footprints as a "hoax made up by people with evil intentions," and branded renewable energy as a "scam." According to The New York Times, he even claimed that environmentalists "want to kill all the cows," and that renewable energy is "destroying a large part of the free world."
Trump’s remarks, which came just weeks before the critical COP30 climate conference in Belém, Brazil, were met with a mixture of outrage, disbelief, and—among some—strategic silence. While world leaders from China to the Marshall Islands responded with new pledges or biting invitations for Trump to witness climate impacts firsthand, the United States’ position on climate policy seemed more isolated than ever.
The diplomatic fallout was immediate. As Politico reported, one European official observed, "the world will take it, because the world has no choice." Trump’s speech was not only the most detailed statement of his climate and energy views since returning to the White House earlier this year, but also a clear signal that the United States was, once again, stepping back from global climate leadership. Just days after re-entering office, Trump withdrew the US from the Paris Agreement—a move that, as Senator Brian Schatz of Hawaii noted at the Climate Forward event, gave China political cover to set less ambitious targets.
Indeed, China’s role in the unfolding climate drama loomed large. On September 24, President Xi Jinping appeared via video link at a UN climate summit, announcing that China would cut emissions by 7 to 10 percent from peak levels by 2035. "The green and low-carbon transition is the trend of our time," Xi declared, urging the international community to "stay focused on the right direction." While some experts and speakers at the Climate Forward event were unimpressed with China’s new targets—arguing they fall short of what’s needed to keep global warming below the 1.5-degree Celsius threshold—others pointed to China's dominance in renewables. In 2024 alone, China installed more solar capacity than the rest of the world combined, and its investments in batteries and electric vehicles are reshaping global supply chains.
Meanwhile, the US government doubled down on fossil fuels. Trump’s administration green-lighted new oil and gas projects, and US Energy Secretary Chris Wright announced plans to return billions of dollars earmarked for green projects to the national treasury. Wright also said he would not attend COP30 in Brazil, and, according to Thred, falsely stated that international climate policy had not lowered global emissions. He defended the administration’s attacks on renewable power at the Climate Forward event, and insisted that keeping coal plants open was essential for meeting rising energy demand.
Against this backdrop, a coalition of 36 former presidents and prime ministers—organized by the Club de Madrid, the world’s largest forum of democratic former heads of state and government—issued an open letter calling for permanent "polluter profit taxes." Inspired by the windfall taxes imposed during the 2022 oil and gas crisis, these proposed taxes would target the profits of oil, gas, and coal companies, making them financially accountable for the environmental damage caused by their emissions. The group argued that such taxes could generate up to $400 billion in their first year, helping to meet the estimated $6.5 to $6.7 trillion needed annually to "reduce and repair harm from climate change, and to ensure a fast and just transition" to renewable energy by 2030.
"It is shocking, considering the insane amount of profits collected by oil and gas companies in the last year alone, that this kind of taxation does not already exist on a global scale," the Club de Madrid’s letter stated. The organization, which includes more than 130 members from over 70 countries, emphasized that only a permanent, international approach could ensure fossil fuel companies contribute fairly to the costs of climate adaptation and disaster relief.
Some governments have already moved in this direction. Vermont and New York have passed state laws requiring fossil fuel companies to pay for climate adaptation, with New York mandating $75 billion in contributions over 25 years—35 percent of which will benefit disadvantaged communities. Internationally, seventeen countries, including Kenya, France, and Barbados, have formed "coalitions of the willing" to impose levies on high-emitting industries such as luxury aviation and fossil fuels, aiming to collect climate and development finance.
Yet, the scale of the challenge remains daunting. As The Council on Foreign Relations observed, Trump’s arguments ignored decades of scientific research—over 99 percent of peer-reviewed papers agree that human activity is driving dangerous warming—and sidestepped the United States’ role as the largest historical emitter of greenhouse gases. By ceding leadership on clean energy to China, the US risks falling behind not just technologically, but diplomatically as well. As Bob Mumgaard, CEO of Commonwealth Fusion Systems, quipped at the Climate Forward event, America’s highways could soon become a "Colonial Williamsburg of internal combustion," with tourists marveling at outdated gas-powered vehicles.
Corporate leaders, meanwhile, are playing what they call "the long game." Executives from Google, Microsoft, and GE Vernova all emphasized that their climate commitments "truly transcend politics and political cycles," even as they acknowledged the practical challenges of supplying ever-increasing energy demand. Microsoft’s Melanie Nakagawa noted the company’s efforts to offset fossil fuel use in data centers by purchasing renewable energy elsewhere. Still, as the world’s hunger for power grows—driven in part by the rise of artificial intelligence and data centers—finding sustainable solutions remains a complex and urgent task.
For many in the international community, Trump’s speech was both a provocation and a wake-up call. As Hilde Heine, president of the Marshall Islands, put it, she wished Trump would visit her country to see the effects of sea level rise and dying coral reefs firsthand. "I feel real pain when I hear your president saying global warming is a great big con," echoed Australian mining magnate Andrew Forrest.
The coming months will test whether the world’s nations respond to Trump’s climate skepticism by retreating—or by doubling down on their commitments. The upcoming G20 meeting in South Africa, COP30 in Brazil, and future international tax conventions will be pivotal moments. As the Club de Madrid’s open letter urges, "fossil fuel companies must be held accountable on a global level, with conversations about fair taxation placed on the international agenda."
With the stakes higher than ever, the world’s response to America’s climate reversal will shape not just diplomatic relations, but the very future of the planet.
