Economics has always been at the root of inequality. From there it has been reinforced by social factors from gender roles to racism and prejudice, only to be solidified in some time periods by the legal system. While progress has been made in some areas, it is surely true we have backslid in others. Inequality will forever be a struggle for societies. We have the idea of equality down pretty well (the Constitution) but in practice it is much more difficult.
Inequality today can be explained because all inequality (be it because of race, gender, sexual orientation, socio-economic status or another factor) exists in the minds and hearts of people. Society can change the rules and make laws but that does not change what people are taught. What we learn as children, right or wrong, is very hard to change. Many people that are brought up with notions of inequality as acceptable or right will never change these ideas. Often no amount of knowledge or education changes the ideas ingrained in us as very young children. Education is certainly the key to changing this, but the reality is that what we learn at home will often outweigh what we learn in the outside world for the rest of our lives. As long as parents and grandparents are espousing ideas of inequality or acting in a discriminatory manner, their children will learn prejudice and inequality will continue to exist.
I think, although significant advances have been made, inequality can be said to exist still among the groups that have been traditionally identified as marginalised by society: ethnic minorities, women and the working class. It still appears that the gender, skin colour and class that you are born into is the most significant factor in determining your life chances and other issues such as whether you are likely or not to end up in jail.
Along with the previous post, I think a great deal of the inequality is caused by the fact that folks who have power and influence (read top 1-5%) have it in their interest to maintain that inequality and not allow a massive upward movement of all the also-rans. This would threaten their position and their childrens' positions and so it is something they have zero interest in doing. Because they have such great influence, many decisions both in the government and in other areas reflect this and so inequality is maintained and increased.
In terms of the national economy of the United States, the disparity between the richest 1% and the rest of the country has never been greater. In fact, it is the largest disparity of all developed countries in the world. I’ve seen reports where the average income of a CEO is anywhere from 140 to 260 times the average wage of the average worker.
In terms of gender, there are still instances where women make less for the same occupation. There was a case in the last two years where a female manager at Wal-Mart was making less than her colleagues.
We also live in an age when affirmative action is still necessary. So inequality is not just solely economic. Bias toward race and gender still play a role in sustaining a system that includes unequal pay because of those biased tendencies.
Societies can change belief and thereby, the way they function. But tradition and the ritual or socioeconomics are very systemic and require fundamental change, usually involving government and nation-wide social movements of the kind we saw in the 1960s. There are such movements today, many facilitated online, but there is still a lot of progress to make. Part of the problem is the class system. America may be the land of opportunity, but clearly there are systemic problems. I wouldn’t say being born into a wealthy family or being born into a poor family is a problem. It is a fact of any social system. But it is, by definition, unequal.
There are many ways to explain inequality today. The explanation that one accepts tends to vary depending on one's political/ideological point of view.
I would argue that the current levels of inequality in the United States are caused at least in part by the loss of industrial jobs and the growing demand for "knowledge-based" jobs. In the 20th century, people with very little education could still make good money in the US by working in steel factories and other such manufacturing facilities. Nowadays, with globalization, these high-paid but unskilled jobs are vanishing. At the same time, the demand for white-collar jobs is increasing, especially in high-pay sectors such as communications systems and banking and finance.
Because of these things, the well-educated are continually getting richer while the poorly educated are not able to increase their income levels. This leads to inequality.