Well, this is yet more evidence, as if anyone needed it, that budgeting for a sovereign nation -- particularly one whose economy the world revolves around -- is qualitatively different from budgeting for a household.
Some questions: Would it be bad for a person to be debt free? A household? A neighborhood? A small company? A large company? A city? A state? A small country? A large country?
Why is it good for companies and people to be debt-free, but bad for countries?
Another way to look at it is that it's not just government debt that's important; there have to be some people who owe other people money or the economy doesn't function. The normal process of business institution-building is founded on the idea of loaning money (again, we usually call this "investment," but it's debt at its base). A good way to think about it is that if you are debt free, that's good for you, but if everyone were debt free, we'd still be living in an incredibly primitive economy.