The cause of the current economic problems is very simple: Bad economics. Instead of closely examining the monetary theory that got us into this mess economists have started playing the blame game. Alan Greenspan blamed Wall Street irrational for making irrational economic decisions the appear to have brought the US economy to the brink of disaster.

On the other hand, Morgan Stanley’s Stephen Roach blames "Greenspan’s blend of politics and ideology" for the current financial mess, arguing that it "led to bad economics and a succession of policy blunders whose severity is only now becoming clear". All that Roach made clear is his ignorance of economic history and sound economic theory.
Dire warnings of an economic collapse plague the US economy | Mint Dollar