Coal miners gave Hillary Clinton a hard no in West Virginia, handing her just 36 percent of the Democratic vote and providing Bernie Sanders with another primary victory.

Clinton really lost the state two months ago, when she said in a town hall meeting that she would “put a lot of coal miners and coal companies out of business.” In West Virginia, where three in 10 primary voters claim a coal miner in their household, these comments rankled.

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In Mingo County, where the unemployment rate is a whopping 14.3 percent, protestors chanted “go home!” at Clinton. Local officials in Logan County (unemployment rate 12.3 percent) told Sen. Joe Manchin that “Bill and Hillary Clinton are simply not welcome in our town,” describing how her policies “have all but devastated our fair town, and honestly, enough is enough.”

One laid-off coal worker summed up the sentiment of many in his state, asking Clinton point-blank last week, “How can you say you’re going to put a lot of coal miners out of jobs and then come in here and tell us how you’re going to be our friend?”

West Virginia’s wholesale rejection of Clinton is all the more devastating, given her past performance in the state. In 2008, she won every single county, beating Barack Obama a staggering 67 percent to 27 percent.

The irony is that Sanders has been a key driving force pushing Clinton toward a more radical environmental agenda. He’s also consistently taken a much harsher stance against fossil fuels.

As recently as 2009, then-Secretary of State Clinton spoke internationally about how “coal will be, for the foreseeable future, part of the energy mix.” Her State Department also boosted coal development around the world, including in Afghanistan and South Africa.

In contrast, in 2009, Sanders spoke at Greenpeace, specifically calling out coal. He’s garnered the support of arch environmentalists including Bill McKibben and Naomi Klein, even calling for an outright ban on fracking.

The Democratic Party’s environmental stance will ultimately benefit Donald Trump the most. Though only 29 percent of West Virginians are Republican, the state’s blue-collar Democrats and Independents are shifting en masse toward Trump. Nearly four out of 10 Sanders supporters in West Virginia say they’ll ultimately vote for Trump in the general election, as do 9 percent of Clinton’s primary supporters there.

The left’s environmental proponents are quick to point out that climate change is a priority for millennials, a generation that just overtook Baby Boomers as America’s largest generation. But millennials also despise Trump; among them, his net favorability is an abysmal negative 57.

But there’s a real risk Democrats’ far-left stance on energy and environment will lose them voters, especially in regions with lots of blue-collar and union workers. Since February 2015, West Virginia, Wyoming and North Dakota alone have shed more than 43,000 coal jobs. That’s not even counting the sweeping layoffs elsewhere in the fossil-fuels industry.

Market forces, including competition from cheap natural gas, have contributed to coal’s glut—but so have counterproductive policies like the Clean Power Plan, which will cost thousands of jobs and reduce global temperatures by a mere .02 degrees Celsius by 2100, according to Cato’s calculations using the Environmental Protection Agency’s own modeling.

If West Virginia is any indication, Democrats are hell-bent on learning the hard way that extreme environmental agendas are bad politics.

Jillian Kay Melchior writes for Heat Street and is a fellow for the Steamboat Institute and Independent Women’s Forum.