If the financial sector does not mostly consist of real banks, taking deposits and lending money to businesses, what do they do? Christopher Ketcham explains, in an article titled "The Reign of the One Percenters," in Orion Magazine:

At one time, the financial sector could be relied upon to allocate capital for the building of things that society needed—projects that also invariably created jobs. But productivity is no longer its purview. Lord Adair Turner, a financial watchdog and former banker in the city of London—the other world capital of finance—recently denounced his class as practitioners and beneficiaries of a “socially useless activity.” Paul Woolley, who runs a think tank in London called the Centre for the Study of Capital Market Dysfunctionality, observed that the “presumption that financial innovation is socially valuable” was a kind of metaphysics. “It wasn’t backed by any empirical evidence,” Woolley told John Cassidy, a staff writer for The New Yorker. Structured investment vehicles, credit default swaps, futures exchanges, hedge funds, complex securitization and derivative pools, the tranching of mortgages—these were shown to have “little or no long-term value,” according to Cassidy. The purpose was to “merely shift money around” without designing, building, or selling “a single tangible thing.” The One Percenter seeks only exchange value, as opposed to real value. Thus foreign exchange currency gambling has skyrocketed to seventy-three times the actual goods and services of the planet, up from eleven times in 1980. Thus the “value” of oil futures has risen from 20 percent of actual physical production in 1980 to 1,000 percent today. Thus interest rate derivatives have gone from nil in 1980 to $390 trillion in 2009. The trading schemes float disembodied above the real economy, related to it only because without the real economy there would be nothing to exploit.

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Finance as practiced on Wall Street, says Paul Woolley, is “like a cancer.” There is only maximization of short-term profit in these “financial services”—they are services only in the sense of the vampire at a vein. There is no vision for allocating capital for the building of infrastructure that will serve society in the future; no vision, say, for a post-carbon civilization; no vision for surviving the shocks of coming resource scarcity. The finance nihilist doesn’t look to a viable future; he is interested only in the immediate return.