Have you seen the commercial President Trump is running on TV this week, touting accomplishments during his first 100 days? In it, he claims to have added more than 500,000 jobs to the U.S. economy. That’s a big number, but we’ve got a bigger one: 7.6 million. That’s the number of American jobs Trump’s threatening in this country’s fourth-largest industry—outdoor recreation.

Last week, Trump signed an executive order asking Secretary of the Interior Ryan Zinke to review every national monument designation made under the Antiquities Act since 1996. The review will look at protections made by Bill Clinton, George W. Bush, and Barack Obama, with particular emphasis on Obama’s controversial protection of Bears Ears in Utah last year.

Standing under the stuffed heads of a buffalo and an elk, as well as a framed portrait of Teddy Roosevelt, Trump announced the order by stating, “The Antiquities Act does not give the federal government unlimited power to lock up millions of acres of land and water, and it’s time that we ended this abusive practice.”

This executive order is the latest offensive in the Republican Party’s war on America’s public land. To recap: You, I, and every other American own roughly 640 million acres of public land in this country. That land makes up not only our national parks, forests, and monuments but also our wildlife refuges and BLM land. It’s a system largely responsible for our proud tradition of outdoor recreation. Your parents were able to take you camping when you were a kid because of our public lands. Our country has huge numbers of wild animals because of our public lands. We have clean air and clean water because of our public lands.

Public lands are what make America great right now—and they’re also a huge revenue generator. In 2015, they contributed $360 billion to the American economy from activities like livestock grazing, energy production, and resource extraction.

All that land is managed on our behalf by the federal government, which is mandated to preserve access for multiple uses while preserving the land for future generations. Despite the need to foster access for campers, hikers, hunters, and everyone else, and despite keeping the land pristine, it still generated $230 billion of conventional energy—oil, gas and coal—in 2015. Yet the GOP is still attempting to sell off that land to extractive industries, and they’re lying to us by saying doing so would be pro-states’ rights and pro-small government. It’s been clearly demonstrated that doing so would lead to less income for the states.

That brings us to Utah, where Bears Ears is located. There, state politicians who have transparently been bought by the oil and gas industry are working against the interests of their constituents to sue the federal government for control of our public lands. Oil and gas bring $2.4 billion a year and fewer than 7,000 jobs to the state economy. Meanwhile, Utah’s outdoor recreation industry brings in $12 billion and employs 122,000 people. And it relies on the state’s public lands to do that. Not only would eliminating public land in Utah threaten outdoor recreation there, but it would actually cost the state more money to manage than it’s currently earning from federal management of those lands.

If the GOP’s efforts in the state are successful, Utah stands to lose much of its outdoor recreation economy, and it will find itself in the red to the tune of $154 million in management fees each year. And that’s according to the GOP’s own numbers.

Let’s expand our view nationwide. During Trump’s first 100 days, we’ve seen legislation proposing the sale of vast swaths of public land, a budget plan that includes cutting the National Park Service’s annual funding by 12 percent, an attack on the Endangered Species Act (90 percent of Americans are in favor of keeping the ESA), and deregulation of environmental protections. Together with this review of national monument designations, our public lands are under unprecedented assault.

That nationwide assault on the places where we recreate outdoors—and the quality of the environment in which we do so—threatens to derail America’s fourth-largest industry. In this country, outdoor recreation accounts for $887 billion in annual consumer spending and employs 7.6 million people. That money and those jobs are reliant on our public lands. Without places to camp, paddle, hike, hunt, or pedal, we can’t sell tents, backpacks, rafting trips, hunting rifles, or hiking boots. And the people who design those things, make those things, sell those things, and who guide those trips won’t have jobs. To be clear, we’re talking about more money and more jobs created by the outdoor recreation industry than the oil and gas and automotive industries combined.

President Trump, if you truly care about saving American jobs and growing the American economy, then start with this uniquely American industry that provides such an amazing quality of life to our great country. You must save our public lands. The American economy depends on it.