This post may have a wonderful title, but I intend to keep it short nevertheless. I am sure my summary can be hooked up to many story on income inequality that circulate and go into much more detail.
There are actually two (types of) charts I want to combine. The first is Branko Milanovic's now famous elephant chart from a 2002 World Bank Discussion Paper. It looks like this:
What is says is that from the global income distribution, the world's lower middle class has been growing, while at the same time the world's upper class saw its wealth increase, but not the poorest of the world nor the upper middle class globally. Also quite interesting is that this growth seems non-zero sum, as capitalist thinkers like to emphasize. Nearly nobody is worse off, and many are better off. Hence, following Rawls, there would be little to worry about.
Yet there is another graph, that shows the decline of the middle class (defined as 2/3 of median income to twice median income) over time between 1971 and 2015 as drawn up PEW Research together with the Financial Times. It is reported in the apocalyptically sounding article "
America’s Middle-class Meltdown: Core shrinks to half of US homes. Society splinters as bedrock of postwar economy is ‘hollowed out’". Let's see what happened:
So while the bulk of the distribution of 1971 is fading by about 1/3 and now almost uniformly distributed, the upper half is growing and the top percentiles are more than quadrupled in their count. To quote the article:
"Since 2008, the number of adults in households in the upper two tiers has grown by 7.8m, outpacing the growth in the number of adults in households in the lower two tiers, where the number of people grew by 6.8m. The middle class grew by 3m over the same period."
The political impact
It is no coincidence that these graphs circulate now that Donald Trump is president elect. The decline of the middle class in the West is raising concerns amongst those who do not benefit from globalization. Why would they favour it then? I see it as a very simple prisoners' dilemma: any party chooses for control over self-interest, when coordination of mutual gains fails. The liberal establishment in the UK and the US has surfed on a wave of globalization, but apart from the Coasts in the US and the City in the UK, people have not seen the benefits of it. People don't care about average, they care about where they are relative to the average. Hence Trump, hence the opposition to CETA and TTIP, hence Brexit, and worse: hence hatred to anything and anybody that is not visibly contributing to one's self interest. People are not more xenophobic than ever, but they don't see the use of migrants, only the hassle. The ones that had always been racist now find legitimacy in this to misbehave. Yet the roots are still in the game theory: if the coordination would work - say, free trade levels up social rights and internalizes environmental costs - people might sacrifice some of their autonomy (power) and direct control, because they trust they will be better off.
The social impact
I have already hinted at the social impact above, referring to Rawls and referring to peoples relative wealth. Of course this is what matters. Absolute wealth is absolutely unimportant from a social point of view. Mind the adjective social: there is nothing social about comparing yourself with the stone age, that is historical. Nobody in this world would have any right to complain when put in historical perspective, as we are all better off. Even the poorest of the poor are not hunted by lions anymore, and in comparison, very weak people now have a fair chance to survive, whereas they would not have stand any chance some thousands of years before. Rawls argument that inequality is fair if anybody improves, is therefor blatantly flawed. For the sake of clarity, let me invert the reasoning above: if people are happy because they have more, they should be less happy if they have less. Hence Napoleon Bonaparte, who did not have an iPhone, should have been very unhappy to have to wait over 100 years before reaching the living standard of today. I believe this reductio ad absurdum shows that Rawls is wrong: deprivation is a relative concept in the minds of people. Imagine you are rich, but you bring your children to a school for the absolute elite of your country. Even if your kids may already be spoiled by you, they will feel dropped behind compared to the even richer kids, who may get a pony instead of a bicycle at ten years old. It is easy to see that this shapes the experience. Going from toys to trauma, it is now understandable that suicide is not the most individual, but actually the most social act, and occurs more frequently in more prosperous society, where the pie is larger and the distribution more unequal.
The economic impact
Finally, the unequal distribution of wealth also has an effect on the economy. Let us stick for now to the US graph above. Assuming that the middle class is the class who spends the share of added value earned. The upper class saves the money and the underclass may have be a cost factor. So the middle class is the motor of the economy, and its number is the fuel. Then we see the paradox that as countries develop, inequality grows, the society gets polarized, and growth slacks. Sadly, in the middle of the 20th century, it took World War 2 to restore the balance - temporarily. Workers in general, and women in particular, could no longer be left behind, as they had witnessed the worst consequences of war.
Bloomberg calls for urgency, quoting an unusual system critic:
"When people like Deutsche Bank are starting to say, 'maybe capitalism needs a form of reinvention,' maybe that's the time to start listening to that," he said during an interview on BloombergTV. "It's not Bernie Sanders; it's a global investment bank."
Digging a little bit deeper in the mechanics of this boom and bust scenario, there are two ways to explain it. The Stockhammer-Onaran story goes like this: national income may come from consumption or from exports, but if an economy is closed, as is the world's economy, but probably also the EU and the US, it needs to come from consumption. Only single regions can benefit from the export-led growth. As a rule, most economies however are wage led. The second story, mine, does not contradict the first, but draws attention to the following logical fallacy: when wages are under pressure and profits increase, these profits go to savings and investments. This brings about an perpetual series of mergers and acquisitions, for cheap. However, these acquisitions only appear cheap because they are statically misvalued. They are worth much less, as there is less demand (purchasing power) for the goods. So the capitalist buys shared or takes over a company, but these share will lose real value soon. Growth comes from technology and investment, not from financial juggling. So as the profits increase we have a boom, for instance the dotcom bubble or the real estate bubbles, but soon after this leads to a bust. In the Financial Times article we do see the trend of increasing polarization taking a step back in 2011. Paul Krugman recently posted the US real GDP evolution on Twitter, arguing the Great Recession was not so unnatural after all and growth has caught up again. So the boom-and-bust scenario may economically lead to some Schumpeterian creative destruction, or maybe even give directions for policy, so that in the end growth continues, but there is no counterfactual: what growth would have been realized in a steady way, without the hassle?
Going back to the elephant graph, we need to extend the economic story. After all, it may be that the western middle class loses its purchasing power, but that the non-west former world underclass now creates demand. It may well be, and I don't know exactly what is behind the graph, but one flaw I anticipate is that the worlds upper class is not only western. Hence the unfair distribution of wealth is not a global redistribution, but it is in fact a global increase in inequality. In every market, those who earn least get less of the pie. Say an Indian worker earns 10 USD a week - I really have no clue - and witnesses an increase to 15 USD thanks to globalization. The Indian businessman, however, goes from 10 000 USD to 15 000 USD, increasing the absolute gap. In general, for the study of wages and remuneration, and because of the social aspect, I believe log wages are more reasonable as they represent relative differences, but for the economic aspect, this absolute difference may matter. The US worker, for instance, might have gone from 100 to 150 USD a week or more, but this gain went to the top class, bought out by cheaper labour outside the West.
Conclusion
There is an elephant in the room and many if not most political actors do not see it. However, the political, social, and economic story that are all linked to the growth of inequality should be clearly disentangled for practical purposes. In each field specific efforts are to be made: politically, the story of coordination needs to be made clear and demonstrated - there are non-zero sum gains to be made and distributed. Socially, more equality will increase the perception of fairness and self-belief, leading to seizing more opportunities like schooling and entrepreneurship, instead of social upheaval. Economically, a stable and optimal distribution of added value, i.e. a fixed wage share more than taxation and whatnot, ensures continued consumption, stable asset prices (!), and hence real, global growth. Failure to convince the relevant actors of what needs to be done on one of the three fields will necessarily also leads to a collapse in the other. We are well on our way to realize such a catastrophe and get trampled by the elephant we do not see.