system
Given the following post, respond as if you're commenting on Reddit:
human
Is Australia the most problematically in-debt nation in the world?

I'm a total amateur but trying to understand why debt is a big deal. It looks like a countries debt isn't as meaningful as its debt to GDP ratio. Better yet is it's external debt to GDP ratio, because countries with extraordinarily high debt like Japan don't seem to collapse cause it's mainly owned by Japanese citizens who don't want to collapse their government. 

Better still is 'international investment position', which is basically the debts we owe other countries, minus the debts they owe us. 

Australia has the one of the world's worst net international investment positions per capita of any debtor nation, according to the International Monetary Fund. 

Yet, I never see this talked about? Wouldn't Australia or another country in that situation need to urgently real in it's foreign debt to underwrite it's economic security and the well-being of future Australians from unprecedented financial crises? I sure don't wanna gamble with my entire country's economic system.
gpt
Australia currently inspire high confidence in their ability to repay debt (AAA rating), got much lower debt to GDP ratio than other developped country, and got self limiting borrowing power through the loan council, used to have a debt ceiling and don't guarantee 100% of the citizen deposits anymore.

Also owning someone debt doesn't mean you can collapse its governement. Debt is just a contract "I give you W and you repay me in X years with Y% of interest payed each Z periods". 

The potential problem with foreign debt is when you borrow money in a currency that isn't yours, because change rate will move and maybe fuck you up. 

(Also if your debt is owned by your own citizen, there may be capital revenues taxes, income tax, VAT and corporate tax on companies where your citizen spend their money so it is cheap debt).