That $5 trillion dollars is not money invested in building roads, schools, and other long-term projects, but is directly transferred from the American economy to the personal accounts of bank executives and employees. Such transfers represent as cunning a tax on everyone else as one can imagine. It feels quite iniquitous that bankers, having helped cause today's financial and economic troubles, are the only class that is not suffering from them — and in many cases are actually benefiting.
Mainstream megabanks are puzzling in many respects. It is (now) no secret that they have operated so far as large sophisticated compensation schemes, masking probabilities of low-risk, high-impact "Black Swan" events and benefiting from the free backstop of implicit public guarantees. Excessive leverage, rather than skills, can be seen as the source of their resulting profits, which then flow disproportionately to employees, and of their sometimes-massive losses, which are borne by shareholders and taxpayers.
In other words, banks take risks, get paid for the upside, and then transfer the downside to shareholders, taxpayers and even retirees. In order to rescue the banking system, the Federal Reserve, for example, put interest rates at artificially low levels; as was disclosed recently, it also has provided secret loans of $1.2 trillion to banks. The main effect so far has been to help bankers generate bonuses (rather than attract borrowers) by hiding exposures.