How has the United States maintained strong growth despite its inequalities?

In the United States, p urchasing power has hardly risen for the bottom 40% of income earners over the past 30 years; the income distribution has skewed drastically against wage earners: one might think that this would lead to weak household and domestic demand. But this is not the case. Why? Possible reasons are: A fall in the household savings rate and/or a rise in household debt; External borrowing; An increase in the fiscal deficit; A rise in the employment rate. We find: Prior to the 2008 crisis, household borrowing and a fall in the household savings rate; Since the 2008 crisis, public and external borrowing.