I am no expert, but I find it better to look at debts credits together. Debt looks scary, but when other countries owe the US trillions too, it balances out somewhat. The net international investment position is an aggregate measure of how much over-leveraged the country is as a whole, and looks much less stark. This combines government debt with citizen assets, which is good and bad - masks federal policy issues, but also accounts for the artificially low taxes in the US and the impact that has on relative wealth placement.