Examines rising alarm over waste of natural resources, and its use by Theodore Roosevelt and his administration to further objectives of conservation and an American form of empire. These objectives encompassed both preservationist and utilitarian approaches, centered on efficiency, but interpreting efficiency in social and political rather than economic terms. These policies revealed an emerging idea of environmental “habitability” that presaged modern interest in sustainability. The suite of policies closely tracked a developing geopolitical worldview, c. 1898-1910. Anxieties over resource shortage were stimulated by acquisition of a formal colonial empire, and the concurrent emergence of the United States as a world power. Connects this awareness to international fears over European powers’ impact upon the non-western world, and concerns over international competition for resource dominance. Documents work by Gifford Pinchot and other government officials, politicians and conservation minded-reformers to curb and/or rationalize resource use. Deals with forests, waterways and irrigation, fossil fuels, soils and rural problems, national parks and other “preservationist” initiatives, and public health. Shows the relationship between this conservationist agenda and similar concerns in other countries. Advances the idea of settler colonialism within an Anglo-Saxon racial hegemony as foundational to Roosevelt’s response to the perceived crisis. Examines contradictions within Progressive conservation over intergenerational equity and over the international outlook that conservationists advocated. Traces the post-1910 attenuation of the conservationist agenda resulting from internal politics conflicts, economic demands within a consumer oriented market system, and external events, especially World War I.