Check this
https://en.wikipedia.org/wiki/List_of_countries_by_external_debtUnited states is number one, China is number ten, Russia is number twenty nine, and Germany is number eight. It means you're wrong if you think strong economy countries aren't in debt.
Debt isn't always bad for filthy rich people or countries, watch Robert Kiyosaki how he use debt to make more money and protect his wealth.
National debt and personal debt are completely different, so don't make such a lame comparison. For example, the United States is the country that holds the world's money printing machine, they can freely export their inflation to other countries with the monetary policy they set. Do you think their government debt, their national debt, is a problem? Or is that just what they want to show the world?
Regarding personal debt, I haven't read about Robert Kiyosaki but let's use you as an example. Can you become rich with debt? Don't take other people's examples but put yourself in that situation to make it more realistic.