Final answer:
Roosevelt's program focused on conserving and managing natural resources, leading to the preservation of millions of acres of public land for wildlife sanctuaries, national parks, and forests, significantly shaping U.S. environmental policy with a legacy that includes the establishment of the National Park Service.
Step-by-step explanation:
Roosevelt's program was aimed at conserving and managing natural resources, and his lasting effect on national environmental policy was significant. His administration condemned the exploitation of natural resources and set aside 148 million acres of forest reserves. Roosevelt established more than 50 wildlife sanctuaries and several national parks, fundamentally shaping the direction of environmental conservation in the United States. With the creation of the National Park Service during the Wilson Administration in 1916, Roosevelt's vision for public land and resource preservation was further institutionalized.
Under Gifford Pinchot's supervision as the first chief of the U.S. Forestry Service, extensive conservation efforts led to the creation of 150 national forests, which amounted to about 230 million acres of public land. This land was set aside not only for preservation but also for regulated use for future generations.
Despite some disagreements with naturalists like John Muir, Roosevelt's policies largely favored the sustainable management and conservation of natural resources, balancing development with the needs of environmental preservation. Together, Roosevelt and Pinchot greatly increased the nation's forest reserves and promoted scientific land management, making noticeable strides in environmental protection.