carbon tax costello nails it, page-59

Australia's Commonwealth Parliamentary Library

"..Net debt therefore, provides a quantitative measure for the degree of debt held by a corporation, a government or a country but is just one measure used to determine their overall financial health. For example, if a government has a large amount of cash and or assets and a large amount of debt it would be better able to handle its debt situation than a government that has a small amount of debt but limited cash or assets..."

http://parliamentflagpost.blogspot.com.au/2011/04/australias-current-debt-position.html