经济不平等是导致美国政治极化的一个长期的根本性原因。美国历史上两个经济不平等最严重的时期也是政治极化最严重的时期。通过考察基尼系数、不同层次的家庭收入和财富的比重等指标,可以发现过去几十年里美国的经济不平等变得越来越严重。经济不平等导致了政治上的分裂,增强了富人对政治的影响力。经济不平等导致的收入差距拉大,会增大两党的政治代表性的差异。同时,经济不平等还巩固和增强了选民的政党认同的差异:中高收入选民更加倾向于共和党,而低收入选民更加倾向于民主党。总之,经济不平等对精英政治行为的根本影响是巩固和增强了他们的政治分裂,也就是说加剧了政治极化。 Economic inequality is a long-term fundamental cause of political polarization in the United States. The two most serious economic inequalities in the history of the United States are also the most serious period of political polarization. By examining such indicators as the Gini coefficient, household income and wealth at different levels, we can find that the economic inequality in the United States has become more and more serious over the past few decades. Economic inequality led to political divisions and increased the political influence of the rich. The widening income gap caused by economic inequality will increase the differences in political representation between the two parties. At the same time, economic inequality has also consolidated and strengthened the differences in electoral party identification: middle- and high-income voters are more likely to be Republicans and low-income voters are more likely to be Democratic. In sum, the fundamental effect of economic inequality on elite political behavior is to consolidate and enhance their political fragmentation, that is to say exacerbate political polarization.