the current downturn is the result of the US moving from an economy based on production to one based on consumption.
With consumption it is possible to earn money and lots of it very rapidly, but it's risky. Handing out loans to consumers, and then collateralize that debt as a commodity is next to impossible to reliably mangae and even more difficult to predict it's risk of failure.
With a production based system, you have to invest significantly in your workforce, their training, health, and standard of living, without immediate returns. However this debt is consolidated and more easily managed, with more predictable risks.
Historically the US was strongest, economically, politically and militarily when money was earned by making and selling a physical product. Now however the majority of what we consume is imported, incidentally the jobs which used to be our bread and butter, have been marginalized. Income has grown, but cost of living has increased more. This is because the jobs which are now our mainstay are retail, and service sector jobs, jobs that don't require much training, come with fewer benefits, and pay less.