US President Donald Trump has reversed a key Obama-era scientific ruling that underpins all federal actions on curbing planet-warming gases. The so-called 2009 'endangerment finding' concluded that a range of greenhouse gases were a threat to public health. It's become the legal bedrock of federal efforts to rein in emissions, especially in vehicles. The White House called the reversal the 'largest deregulation in American history', claiming it would make cars cheaper and reduce costs for automakers by $2,400 per vehicle.

Environmental groups have voiced their outrage, stating that this decision is one of the most significant rollbacks of climate change efforts ever attempted and are set to challenge it in the courts. Speaking in the Oval Office, Trump described the 2009 ruling as 'a disastrous Obama era policy that severely damaged the American auto industry and massively drove up prices for American consumers.' He labeled the ruling as the legal foundation for what he called the 'Green New Scam', criticizing the Democratic climate agenda.

The Environmental Protection Agency (EPA) first recognized the dangers of greenhouse gases in 2009, determining that six key gases, including carbon dioxide and methane, posed a danger to human health. With Congress unable to pass climate legislation, the EPA finding became essential for limiting emissions from various sectors. Experts have expressed concerns about the rollback's potential health impacts, suggesting it could lead to numerous additional premature deaths and increased healthcare costs due to higher pollutant levels.

Moreover, reversing this finding may not only influence domestic policy but is likely to create uncertainty within the U.S. auto industry, where less fuel-efficient vehicles could struggle in international markets. Although the Trump administration claims significant cost savings will result from this measure, critics argue it could lead to higher long-term costs for consumers. The future of U.S. climate policy hangs in the balance as environmental advocates gear up for legal battles over the changes.