The continental United States is composed of 2.5 billion acres. Roughly two thirds of the land is owned by individuals and the remainder is owned by the public. In other words there is nearly 900 million acres of land that is collectively owned by "We the People".
Currently all of this public land is being managed by the Department of the Interior, the Bureau of Land Management, the Department of Fish and Game and the United States Forest Service. The agencies created by the Executive Branch of the government control most of the land and natural resources in the western United States.