I attended a lecture on the Credit Crunch last week. Among the bullet-point conclusions, the speaker included

The unwinding of Anglo-Saxon debt will slow economic growth for years.

He explained, without prompting, that the choice of the term 'Anglo Saxon debt' was because it is specifically the English-speaking Western™ countries (UK, US, Canada, Australia, NZ) that have had the biggest debt binges. And why should the unwinding of the debt slow down growth? Because as you say

Financiers, now unchecked by regulation or restrictions on leverage, can monetize many kinds of future revenue streams today, generating instant profits they and their clients can capture.

Monetizing future revenue streams means that several years' worth of future economic growth has already been realised as profits of the financial sector in the past 10 years (explaining the GDP - that is, income - boost coming from the financial sector). A few years of economic growth will be spent just making good on the liabilities incurred in the process by the productive part of the economy.

A vivid image of what should exist acts as a surrogate for reality. Pursuit of the image then prevents pursuit of the reality -- John K. Galbraith