Unlike many population forecasts, the thesis of this paper is that present and prospective effects of population growth in the United States have been exaggerated in comparison with other aspects of population change. The effects of national population growth have been confused with those of growing affluence, changing technology, and concentration of the population in metropolitan areas. Special attention here is given to the possible social effects of the present slowing population growth in the direction of a stationary or even declining population such as the aging of the population, the problems of "depopulation" in a large part of the United States and the smaller size family. These may involve less mobility, a longer life cycle, more accepting attitudes toward death, less crime and violence, more pressure for foreign labor, and a possible (but dubious) trend toward conservatism and stability. The author concludes with a discussion of some possible effects of population changes on U.S. relations between the U.S. and Latin America. (Author)