The authors, Richard Wilkinson and Kate Pickett, discuss this at length in the audio program. But the short answer is that more equal societies do better in terms of overall health and happiness, and in terms of reduction in crime.

Inequality in wealth, they argue, is the greatest driver of violence in society.

Hey John, thanks for entering into this conversation. Your comment has inspired me to type away for a few minutes here.

You write that the USA is the most affluent with the highest standard of living in the world. As a police officer, I wonder how you can say that, because I am sure that you are aware many people in the USA do not have high standards of living. The USA, amongst industrialized nations, has one of the highest rates of violent crime (and of incarceration, many for offenses that are considered not violent, like drugs—no doubt in thanks to the sweeping increase of privatization in the prison industry. More prisoners=more profit for investors. More prisoners means more riches for the wealthy.)

The USA has one of the greatest disparities in wealth between rich and poor. (Thanks to capitalism.)

You can call it a classroom theory. But if you listen to the radio program, then you will hear the argument applied to real world socio-economic-political situations. The authors make a clear, persuasive and convincing case for how disparity in wealth, and the behaviors that lead to that disparity, affect people on a daily basis (increased crime and acts of violence.)

For example, some people make money off of war, and related policies of American Exceptionalism—international dominance. Some make money from stealing from other lands and peoples. All the while others lose their jobs when, for example, transnational companies relocate manufacturing to overseas.

(All of which lends itself to the idea that being rich as a measurement of success is not the best for society.)

For me, it basically comes down to the idea that people—all people—deserve to be, and ought to be, treated well. That includes, again, all people, regardless of age, gender, sexual orientation, ability, religious or ethnic background, or nationality, etc.

Blaming poor people for being poor, when the forces enabled by Wall Street (and a Wall Street friendly government) constantly-erode-the-likelihood of widespread economic security and stability, doesn't make sense.

Poor people are the victims here, in a long-long-long, ages long, war of rich against poor. Most people just want to get by, and have enough to live a decent and happy life. Maybe the problem is that some people just can't get enough. Some people feel the need to be at the very top of socio-economic hierarchy. Some people aren't satisfied unless they have control over other people. And we have socio-cultural and political systems that enable and 'reward' people who behave with intense ambition to 'get ahead.'

So it's a cultural phenomenon. And as long as some people view themselves as superior to others, whether it is based on race, age, gender, nationality, or ambition to get rich, then we will constantly have people who are willing to put others down, separating, comparing, contrasting differences in order to justify their own motives and ambitions for climbing up, even while others are pushed down.

Wealth is great. So long as it doesn't necessitate oppression. So long as it doesn't involve racism, or war, or any kind of other violence—including judging others based on political or cultural differences.

I tihnk that one of the reasons that many (what you might consider to be) 'socialist nations' aren't as wealthy as 'capitalist nations' is because of sanctions (which are aggressive) placed by capitalist nations.

Competition
Competition has its place. But when competition gets to the point of subduing, subjugating, demeaning, or behaving in ways that are downright cruel (or even just unfriendly,) then what good does that do—except to divide, and to open up corridors for greed and avarice, toward the pursuit of conquest.

There is enough (air, water, space, land, earth, money, time, love, etc.) in the world for everyone to have enough, and to live decent and happy lives. Why some have so little when others have so much is a matter of economic and distributive justice. It is not so much a matter of the poor being to blame for their poverty.

That's what I think.

To answer your question about places that have as good or better standards of living than the US: again, you can find some answers to your question in the radio program linked above. Some of the examples mentioned in the program include Germany, France, and Scandinavian nations.

Of course, there is the likelihood that Cuba would rival the USA in terms of wealth, if it wasn't subjected to such cruel and unusual sanctions.

The point here, again, is that we can have it all. We can have a wealthy, prosperous, industrious society, and society where everyone can have a decent, meaningful, and dignified job.

We can take care of the planet, we can take care of ourselves, and we can take care of each other.

It's a question of human v. nature, and human v. human, versus —human with nature, and human with human.

which includes life expectancy, literacy, and material standards of well being, the US ranks 12th behind Iceland Norway, Australia, Canada, Iceland, Sweden, Switzerland, Japan, Netherlands, France, and Finland. Most of these countries, like the US, have what are considered mixed economies (no one is purely capitalistic or Marxist, so that dichotomy is pretty meaningless these days). The "mix," of course, can vary.

The HDI and income (or wealth) distribution are related. One way to measure income distribution is with the Gini Coefficient, which is stated as a ratio between 0 (perfect equality) to 1 (perfect inequality). For example the Gini Coefficients in Sweden and Nambia are .23 and .70, respectively.  On average, a country's HDI ranking increases one rank for every 0.0948 descrease in it's GINI Coefficient. So, yes, there is a relationship between equality and well being. It is not a perfect relationship, but it is there...on average.