In W.W. Jacobs’ 1902 short horror story The Monkey’s Paw, the cursed paw grants three wishes, but in unexpected and malign ways. For the US automotive industry, President Donald Trump has had a rather similar effect. As soon as he was elected, carmakers started urging Mr. Trump to rethink President Barack Obama’s planned vehicle fuel economy and emissions standards for 2022-25. Last week, the Trump administration set out its proposals for fulfilling that request: it intended to abandon the steady tightening of the standards envisaged by Mr. Obama, and instead freeze them at their 2020 levels for the six years 2021-26.

Far from celebrating the success of its lobbying campaign, though, the US automotive industry gave the administration’s plans a distinctly tepid response, suggesting that the proposals should be just a starting point for further negotiations. Having egged on Mr Trump, the industry is now trying to rein him in. Car companies argue that they had legitimate grounds for complaint about the Obama administration’s plans.

The standards were set as the result of a 2011 agreement between the administration and 13 leading carmakers, which included a commitment to a “mid-term evaluation” in 2017. After Mr. Trump’s unexpected election victory, the Environmental Protection Agency hurried that evaluation through in the dying days of the Obama administration, concluding swiftly that the existing plans were just fine. Meanwhile, the slump in oil prices that began in 2014 was making it harder for manufacturers to meet the standards.

Compliance is based on the average performance for the cars produced by each manufacturer, and cheaper petrol blunted the incentive for consumers to buy more fuel-efficient vehicles. Having exceeded the fuel economy standards by comfortable margins in 2012-15, the industry fell short in 2016 and 2017.