Theodore Roosevelt heavily praised the work of young Leopold to conserve vast areas of land and forest for recreation and the enjoyment of sport hunters. Leopold himself called predators "varmints" when he was as a young Forest Service worker: he advocated for their removal so that ranchers and big-game hunters could go about their business in peace.
But eventually Leopold changed his mind, and he decided he wanted the Forest Service to ban hunting, ranching, and destructive lumber practices within wilderness boundaries.
Those ideas did not fly with the government of the 1910s. After the Forest Service transferred Leopold to Wisconsin, and after he established the academic discipline of wildlife biology at the University of Wisconsin-Madison, the Forest Service came around and adopted many of his ideas.
It turns out that a guy writing from the point of view of hunted animals was a revolution in nature writing... and it saved a lot of cool animals.