I don't really disagree with you but you're operating on the assumption that the Japanese Gov't will continue playing "the game". Bear in mind there is absolute

I don't really disagree with you but you're operating on the assumption that the Japanese Gov't will continue playing "the game". Bear in mind there is absolutely nothing stopping them simply declaring that they have paid back all debts. Hyperinflation happens in countries that were collapsing anyway. Under other circumstances, you could call it "quantitative easing" just like the USA has been doing, or who knows what they will call it, but mark my words, that debt will never be repaid, or if it is, it will be with "new money". If you doubt me, answer this quesrtion - why is anyone still lending to the Japanese Gov't? The answer is of course that it's not real debt. You can't have real debt to an entity that can print the currency the debt is based on. The risk is not that the Gov't cannot repay, the risk is that inflation will reduce the value of the payment, and the 1% interest tells you the assessment of that risk.