The article thoroughly analyses the history of the American Environmentalism as a socio‐political movement and follows the evolvement of the early elitist Conservationist Movement into a mass Green Movement based on public participation. The importance of Conservationist principles in the U.S. state policy greatly increased during the first half of the 20th century, especially during the Progressive Era under the first President‐conservationist Theodore Roosevelt (1901‐1909). The economic revival after the Great Depression of 1929‐1933 included development of environmental and tourist infrastructure with mass participation of the civil society. However, the contemporary U.S. Green Movement was formed during and right after the World War II, as a natural consequence of the smart policy pursued by the President Franklin Delano Roosevelt as part of his “New Deal” course. By 1970‐1980s, it already included three directions: the traditional Wilderness Preservation, the Anti‐Nuclear Movement and a combination Anti‐Toxic Movement/Environmental‐Justice Movement (known as NYMBY). Special attention is paid to its basic forms — the environmental non‐governmental organizations (NGOs) and Green political parties. It is concluded that the variety of environmental NGOs — older and newer, national and local, information‐ and agitation‐oriented, advocacy practicing and political lobbyists, etc.— are grassroots of the environmental movement in the U.S., mobilizing civil support and creating an electoral base for Green political parties both at the state and federal level. The author investigates their present condition and perspectives, strategy and tactics of their social and political activities. At present, the popularity of “green ideas” in the American society is still inadequate for the Green Party U.S. to provide a real competition with the two main political parties — Democratic and Republican — at the federal level, even in view of its social‐democratic orientation. However, “The Greens” are successful at the local level. Popularization of “green ideas”, mobilization of followers among the civil society, environmental legislation lobbying and strengthening of the environmental justice system currently remain the main tactics of American environmental organizations.