America’s Income Polarization and Its Causes Wang Rongjun (29) Deteriorating generally since the 1970s, the division in American society betwee n the rich and the poor has shown two different trends of development after the mid1990s according to official sources. On the one hand, the relative position of middle and lower income citizens on the echelon of income and distribution ha s been stable with a slight rise, and the inequality of income and wealth is all eviated. On the other hand, the income and wealth of the richest citizens, who a re a tiny minority of the population, are increasing at a speed far higher than those of other citizens. The author holds that the two trends are not contradict ory to each other and both are the result of the economic prosperity and the cha nge in the government’s economic policies.