I'm happy to see frank and intelligent conversation about rent. There seems to be a general understanding that the wages earned and the capital inherited by the very tip of our society does not speak to high levels of merit but instead to some form of malfeasance or at least market failure.
But when pressed to pronounce what mechanism explains these impressions, theories depart - sometimes violently. There are hundreds of thousands of wealthy families in this upper crust and hundreds of millions of people churning in the domestic system that in part begets it. What's more, the finances of the US are owed to far more than domestic productivity - for example its role in the IMF and World Bank as well as its being the defacto fiat currency make international activity, macro- and eventually micro-, spanning between a billion or two people crucial to understanding its economy.
Any explanation of the impression that the class society forming in America is not due to actually earned wealth must be sufficiently complicated to capture around _2 billion_ people and close to a half of the globe! This is a tall order to demand of a blog post.
In any case, let us examine some of the questions the author asks - in particular about finance.
> Why does finance make so much money? Can it really cost that much to do what financial intermediaries do?
There's a number of reasons. Moral hazard, quite plainly. Regulatory capture (http://www.propublica.org/series/fed-tapes) too. These are domestic explanations and do go to some length to explain how these powerful enterprises are able to meet with law enforcement and regulatory bodies. Others say that HFT, legal barriers to trading, and delayed entry into IPO concentrate the gains of Wall Street into small hands. On the macro side Piketty offers a simple and compelling mathematical model (plus data to back it) that suggests that large wealth all on its own balloons exponentially over smaller wealth because both grow as an exponential over time but large starting wealth increasingly will win out in terms of total proportion - this would be exacerbated by the savings rate available to those 'in the know' of the finance industry (whose full time job it is to grow wealth through investment and speculation as fast as possible).
But in a country where it's difficult to find investments that grow fast enough to beat inflation, where do the mammoth amounts of growth that sustain and feed the highest levels of American finance come from? Outside the country, unfortunately. Take Soros who seems to have wizard like capabilities to predict the future given his alien levels of success 'speculating' on currency exchanges and international companies. Soros does not speculate on markets - at least not in the traditional sense. Nor do the top brass. Soros actively partners with the US government to install organizations in countries around the world encouraging their 'transition' to foreign investment - usually through revolution and regime change.
He, others who do the same, and those others in the sphere of 'civil society', are able to invest early in existing and new international companies as American companies consume the revenues and bring the customer base of newly freed local resources to the international community. The US government is happy to partner here because it can engineer regime change in its and its allies favor but launder the activity through private citizens and companies - this allows it to continue to wave the banner of self-determination, of individual rights and of international law.
Do these things count as rent seeking? Probably. Actually, almost certainly. But its important to understand how complicated - and more importantly opaque - the system that benefits the few is. I hope the conversation continues to make it mainstream - maybe some day we will be able to have a mass informed debate.