According to this article, Japan reached an enormous debt/GDP ratio of about 250%.
The first two answers from here illustrate more about the structure of the debt. My highlights are:
- most Japanese Government Bonds (about 90%) are held by citizens of Japan
- much of that debt is owed by one branch of the government to another, net debt held by the public is only 134 percent of gross domestic product, not the widely quoted figure of 240 percent.
- it has a tax rate of just 35% of GDP, so it could in theory raise taxes by another 10% to pay off debt if it did become a problem
Question: since the tax rate is fairly low and a significant part of its debt is owned by its population, why not raise tax rates instead of borrowing from population?
As the Japanese populace ages, people are going to start withdrawing from these funds making it increasingly difficult to finance the debt within the country. [...] the savings rate for younger people in Japan is also falling indicating that the fewer younger people in Japan will also not be contributing as much per person [...] Japan will have to venture out into the broader world in order to roll over it's massive debt.
. Of course, these are problems on the long term.