Google on the topic, I found some pointers leading to this pdf, see if it sufficiently trustworthy or if there are better sources. The ratio is Total Credit Market Debt to GDP (whatever that exactly means).
Unfunded liabilities? He does say debt, and not national debt.
maybe private debt + government debt?
All debt is over 350% of GDP. This does not include unfunded liabilities, IIRC. The reason all of this debt has been acquired has been extraordinarily low interest rates have encouraged Americans to borrow money.
Read this.
I had no clue about what sort ‘debt’ is referred here. But then I clarified things with my friend, who said that debt in this context means all outstanding liabilities in the economy, not just government debt. So total US debt is basically a sign of the new money being created, as credit.
Debt in excess of your current GDP basically means your future is that much poorer. Debt and inflation is the acceleration of future income to present consumption. That is the true nature of debt that people with high time-preference don’t understand. When people are middle-aged and hit a rough patch, but they’ve still got that onerous mortgage they thought nothing about when they were 35, that’s when they realize how they bartered future wealth for present consumption. There is a good reason for historic aversion to debt in most cultures.