How bad is government debt?

To many people the sums involved are so large, there seems something instinctively wrong, even dangerous, about allowing the government to borrow so much. As Mrs Thatcher said, she was brought up a grocer’s daughter and  she learnt how to balance the books.  Why should the government be any different? Also, if a government has so much debt, is there not a cost to future generation?

http://www.economicshelp.org/blog/6767/debt/how-bad-is-government-debt/