National parks are often called "America's best idea," per writer and historian Wallace Stegner, who said of national parks:
“...the best idea we ever had. Absolutely American, absolutely democratic, they reflect us at our best rather than our worst.”
According to the National Park Service itself, Americans were so inspired by the beauty of the land, they felt compelled to protect it from development. Today, the mission of NPS reads as follows:
The National Park Service preserves unimpaired the natural and cultural resources and values of the national park system for the enjoyment, education, and inspiration of this and future generations. The Park Service cooperates with partners to extend the benefits of natural and cultural resource conservation and outdoor recreation throughout this country and the world.
NPS works around the country to preserve ecosystems and history alike, protecting species of all kinds and educating the public in the process.
But according to some experts, the pervasiveness of national parks around the world has also led the public into a false sense of security that the most beautiful lands are adequately protected. Erik Solheim, the former head of the U.N. Environement, writes for Time:
Less than 20% of the world’s key biodiversity areas are completely covered by protected areas, and fewer than half of threatened species have their range sufficiently covered. Enormous amounts of wildlife, plants and animals both, are undefended by park rangers or the law.
According to a May 2019 report from the U.N. one million of the world's eight million species are threatened with extinction due to human interference. The report lists five main causes of species loss, including direct exploitation of organisms, climate change and pollution.
Solheim warns that protection of land and species cannot be limited to national parks—the smallest areas of nature ensure the function of large-scale ecosystems after all. In this way, national parks pull focus from the land most Americans interact with on a daily basis. As Solheim writes:
...nature’s humblest dwellings and specimens are every bit as worthy of reverence as the great national parks.
Solheim presents a real problem, but the only way to resolve it is through education. There is no better place for environmental education than national parks. And according to U.S. News & World Report, many Americans are taking the hint:
Today, 60 national parks in the United States draw more than 200 million visitors a year to unique natural wonders and unforgettable terrains.
Embrace its mission, as educator, to become a more significant part of America's educational system by providing formal and informal programs for students and learners of all ages inside and outside park boundaries...Education should become a primary mission of the National Park Service. Budgets, policies, and organizational structure should reflect this commitment.
But ecotourism is a double-edged sword. On the one hand, the so-called "future generations" are enjoying the lands set aside for their continued awe and reverence. But on the other, tourism means cars, infrastructure and pollution drawn specifically to the areas the government is trying to preserve. KQED explains:
To make an area accessible to visitors, infrastructure has to be built and transportation has to be arranged. The revenue generated for local economies is often seasonal. Areas may start to cater to more tourists, over time changing the landscape that we are trying so hard to protect.
Beyond problems with overcrowding and pollution, national parks also invite tourists directly into natural habitats. Although no visitor to a national park is encouraged to interact with animals, human presence will have a ripple effect upon the entire ecosystem:
Sometimes increased human interaction with wildlife can be degrading or disruptive to the balance of a natural area’s systems. Wildlife can become habituated to people, or change their behavior to avoid people, decreasing their use of habitat around trails as more people come along.