As a person who has lots of student loan debt (and whose wife has even more), and will at some point buy a house, I understand the desire to be debt free.
But with my rudimentary understanding of economics / personal finance, it seems to make sense that people / businesses / governments often utilize debt as a way to make investments that improve things. Students loans for example, ideally secure an education that will increase your earning power. Same with a small business' investment in an upgrade of its technology / workforce. You go into debt to get something out of it (though not necessarily get out of debt). If you look at business' balance sheets, I imagine most of them are in some sort of debt (even very successful ones). I could be way off here, especially when it comes to global corporations. Governments utilize debt to finance capital upgrades and other nice things.
I think its perfectly reasonable for individuals to carry a manageable amount of debt throughout their lifetime (though I'm not really sure what happens with debts after someone dies). Can you sustain unreasonable amounts of debt throughout your lifetime? No, but neither can governments. If you're like the US and the pinnacle of security for an investment by a bank, then you could borrow like crazy for your whole life, but I imagine that's limited to people like Bill Gates, orgs like Exxon / Apple.