I am currently reading Hall's and Klitgaard's Energy and the Wealth of Nations (2012). In it, they mention the US international debt o $8.000 billion. Which can only be repaid by economic growth (fuelled by cheap oil and gas) or by (hyper) inflation. As the first scenario is unlikely, the second resembles that of the Ottoman default.

As the US Gini index is expected to rise to that of Mexico's today (0,55) (which fits the inflation scenario) it means the end of the middle class, thus the end of internal stability.

Expect hard poverty and more social erosion.