This chapter offers an in-depth account of American public opinion about global warming (GW). Surveys of nationally representative samples of American adults have indicated that from 1997 to 2024, large majorities of Americans held “green” opinions: GW has been happening and caused by human activities; if unchecked, GW will continue, be a serious threat, and merit government attention. Large majorities of Americans have supported a wide range of mitigation policy approaches. In 2024, more than one in five Americans considered GW to be extremely important to them personally. Political candidates have attracted votes by taking green stances and have lost votes as the result of voicing skepticism. Green majorities have appeared consistently across the United States and on many aspects of climate change. Even majorities of Republicans have held green views. Thus, lack of substantial legislation mitigating future warming is unlikely to be attributable to the public not being “green enough.”