Donald Trump and the rest of the Republican Party are in danger of ignoring an important global trend: Politicians who deny the risks of climate change are losing power to those who adopt a less reckless approach to greenhouse gas pollution.

The presumptive Republican nominee has taken an extreme and unscientific position on global warming. In March, he told The Washington Post that he is “not a great believer in man-made climate change.”

{mosads}And earlier this month, he showed his ignorance of the great determination across the world to cut greenhouse gas emissions when he claimed in an interview with Reuters that “at a minimum” he would, as president, renegotiate the landmark Paris agreement on climate change that was reached between more than 190 countries at a United Nations summit last December.

Trump will not be able to renegotiate the agreement, but he could weaken the national contribution to global action that was pledged by the United States ahead of the Paris summit, transforming his country from a leader into an international laggard. However, he should be aware that, in the 12 months leading up to the Paris summit, two of the world leaders who had most prominently dragged their feet on climate change were dumped out of office.

First, in September 2015, Tony Abbott, the Australian prime minister, was ousted after he was successfully challenged for the leadership of the Liberal Party by Malcolm Turnbull. Abbott had been strongly criticized by Turnbull for ignoring the scientific evidence for man-made climate change.

A month later, Stephen Harper, the Canadian prime minister, suffered a trouncing in a general election. His victorious opponent, Justin Trudeau, had highlighted during the campaign Harper’s poor track record on climate change, including his rejection of the Kyoto Protocol.

The humbling of Harper and Abbott, who are both conservatives, indicates that climate change denial is for losers. By contrast, David Cameron, the leader of Britain’s Conservative Party, won an outright majority in last May’s general election with a clear manifesto commitment to implement the U.K.’s Climate Change Act and its target of reducing annual emissions by at least 80 percent by 2050.

Indeed, the U.K. has demonstrated that real conservatives do not need to deny the risks of climate change. Margaret Thatcher, for instance, had already won three successive general elections when she warned the U.N. General Assembly in November 1989 of “change to the sea around us, change to the atmosphere above, leading in turn to change in the world’s climate, which could alter the way we live in the most fundamental way of all.”

Since Thatcher’s speech, the U.K. has cut its annual emissions of greenhouse gases by about 38 percent while increasing its gross domestic product by more than 60 percent. This is undeniable evidence that economic growth and reductions in greenhouse gas pollution can be achieved together.

Few people outside the United States understand how Trump and the Republican Party can seriously expect to be elected while denying the risks of climate change. America’s leading experts at the National Academy of Sciences have been sending the unambiguous message for many years that the potential impacts from man-made climate change could be devastating. So when American politicians disregard the verdict of many of America’s finest minds, they look not only reckless, but also unpatriotic.

The whole world can see that the U.S. Congress has been blocking federal legislation that could raise the level of action by the world’s second-biggest emitter. And it is ordinary citizens in the United States and across the globe who are bearing the consequences of bad lawmaking by the Senate and House of Representatives. American families and businesses are being put in harm’s way as sea levels are rising along their coasts and they are exposed to rising probabilities of heatwaves and other extreme weather events.

That is, no doubt, why a recent opinion poll found that 63 percent of Americans regard global warming as a serious problem, with 76 percent of those aged 18 to 29 expressing concern. And a survey of registered voters in March concluded that 43 percent would be more likely to back a presidential candidate who strongly supports taking action to reduce global warming, with only 14 percent indicating that they would be less likely.

So-called “millennials,” aged 18 to 34, are now the largest group of adult voters in the United States. It is no surprise that they are the target of a campaign by Tom Steyer’s Next Generation organization to make climate change an election issue in seven key states.

If Trump and the Republican Party continue to deny the risks of climate change, they are likely to lose not just the battle for the White House, but also the Senate.

Ward is policy and communications director at the Grantham Research Institute on Climate Change and the Environment and the ESRC (Economic and Social Research Council) Centre for Climate Change Economics and Policy at the London School of Economics and Political Science.