* Country A owes $100M to Country B
* Country B owes $100M to Country C
* Country C owes $100M to Country A
Here, the "world debt level" is $300M. But if country C pays $100M to country A, who then pays it to country B, who then pays it to country C, you'll have settled all three debts and no net money changed hands.If you multiplied all the debts here by a factor of 1,000,000, you'd get a "$100T fiscal timebomb" for each country. But how much of a big deal is that in this hypothetical scenario when they don't, on a net basis, actually owe any money at all?