While the details of the connection would of course require a long article to discuss, I think the basic observation involved is simple. Just compare these two

While the details of the connection would of course require a long article to discuss, I think the basic observation involved is simple. Just compare these two facts: (1) Americans expect to be able to get 30 year mortgages at rates around 3 percent; (2) Americans expect to be able to invest their retirement savings in stocks and bonds with a long term rate of return of 8 percent or more. These two facts make no sense when put together unless somebody is putting a massive thumb on the scales somewhere. In a free market such a situation would be impossible, because nobody would have any incentive to lend money for 30 years at 3 percent when they could just invest it in stocks and bonds over the same time horizon and get 8 percent.