人口结构变迁与美国两党博弈的政治效应分析OACHSSCD

The U.S.two-party competition is no longer merely a recurrence of its domestic political cycle;it has become a deep-seated independent variable directly shaping the international relations landscape of the 21st century.Its spillover effects pose direct and profound challenges to China and the world alike.Population is a fundamental,comprehensive,long-term,and strategic element of national development,and core structural factors such as education level,ethnicity,and age shape individuals' political attitudes and influence their political participation and voting.In response to the concerns of young,elderly,and minority voters,the two parties continually adjust their political agendas in a targeted manner,shifting the focus of both campaigning and governance toward issues with greater mobilizing effects.Using data from American National Election Survey(ANES),this paper analyzes the impact of the population structure dynamic on the Republican and Democratic parties,and systematically reviews the strategic choices of the two-party competition throughout history.Findings reveal that the strategies of the two parties exhibit distinct antagonism and instrumentalism:the Democratic Party seeks to transform demographic advantages into electoral victory by strengthening social security,advancing climate issues,and conducting systematic voter mobilization;the Republican Party,by contrast,emphasizes exploiting cultural anxieties and modifying electoral rules to consolidate its traditional base and expand emerging support.Ethnic diversification and the rise of the younger generation are,on balance,more favorable to the Democrats,while population aging may help the Republicans broaden their voting foundation.Nevertheless,neither party holds an overall decisive advantage,and both will continue to adjust their campaign strategies dynamically in the future.Although population structure is not the sole determinant of the two-party competition,it remains a key variable for examining changes in America's political map and the competition between the two parties,offering a new analytical perspective for understanding their competition.