working to complete a transcontinental rail system. Much of the latter grants intentionally included mineral and timber-rich lands so that the railroads could get financing to build. Again, the hypothesis was that the railroads would sell off the land to get money. Ultimately, however, it turned out that much land west of the Missouri River was not ecologically suited for homesteading because of mountainous terrain, poor soils, lack of available water, and other ecological barriers to significant settlement. By the early 20th century, the federal government held significant portions of most western states that had simply not been claimed for any use. Conservationists prevailed upon President Theodore Roosevelt to set aside lands for forest conservation and for special scientific or natural history interest. Much land still remained unclaimed even after such reserves had been initially set up. The US Department of the Interior held millions of acres in the western states, with Arizona and New Mexico joining the union by 1913. US President Herbert Hoover proposed to deed the surface rights to the unappropriated lands to the states in 1932, but the states complained that the lands had been overgrazed and would also impose a burden during the Great Depression's cash-strapped state budgets. The Bureau of Land Management was created to manage much of that land. Rebellion Various bills intended to transfer federal public lands to western states had been proposed after 1932, all of which failed to garner much attention, let alone action. Among key objections to such transfers were the increasing value to the federal treasury of mineral lease receipts and complaints that the "crown jewels" of the national lands holdings, the National Parks, could not be managed adequately or fairly by individual states. Yellowstone and Yosemite National Parks were considered to be national treasures, and few legislators would concur with turning them over to the states. The spark that turned these complaints into a "rebellion" was the enactment in 1976 of the Federal Land Policy and Management Act, which ended homesteading and so the federal government would retain control of the western public lands. The act sought to establish a system of land management by the Bureau of Land Management. The Act required the bureau to plan land use accommodating all users and specifically named ranching, grazing, and mining, but it also introduced formal processes to consider preservation of the land from those uses. The newly-elected Senator