I devoted some of my graduate school experience to the US History of Economics during the Cold War.
The shortsighted comment here earlier made me laugh, as to break down the collapse of the Soviet Union on simple economics is completely ignoring larger social and political maneuverings that were far in place ahead of Gorbachev. However, it has become, sadly, the popular convention here in the West and in some Eastern European countries.
The US system has been broken for quite some time. Doing a historical analysis (and in depth analysis of the economics and looking at various sources etc.) would show that US economics have (for lack of a better term) been on weak footing since the 1980s (and as one colleague has mentioned to me, Reagan's "voodoo economics") and I'd make an argument since 1968-1969 there were some trouble signs that were being ignored.
Anyways, I don't have the time, nor the patience to detail all of this. There's been enough, empirically (and from other schools of thought as well, the marxists make me laugh) that to educate yourself, just google scholar the subject matter and read.