Any kind of property requires violence to exist. If I say "this is my land" and you disagree, the only way I can enforce my claim is through violence. Debt is just a specific case of a general phenomenon. (This applies to communal property, too.)
> Before the US destroyed Libya, it had the highest GDP in Africa
Do you have a source for this? I see Libya's GDP circa 2005 at $41 billion (in 2005 U.S. dollars) [1]. South Africa's 2005 GDP was $260 billion in current U.S. dollars [2] (bit over $200 billion in 2005 U.S. dollars [3]).
[1] https://en.wikipedia.org/wiki/Economy_of_Libya
http://www.globalresearch.ca/libya-from-africas-richest-stat...
The debt motive for the invasion makes little sense. American banks made more money on Ghadaffi's Libya [2].
[1] http://data.worldbank.org/indicator/NY.GDP.PCAP.CD?locations...
[2] https://www.nytimes.com/2016/06/14/business/dealbook/libyan-...
In "original" societies it is not abnormal for 50% of males to die violent deads. In our societies it is less than 2% as far as i remember. Including two world wars!
So the violence of debt is not that relevant in the big picture.
You borrow £20 from your friends, if you don't pay there is moaning but not usually more. You borrow £100k for a mortgage and don't pay and they may change the locks and put someone else in your house but don't usually hit you.
The United violence has nothing to do with debt.
You can't put a man into debt unless you have the capacity for violence to enforce it. He doesn't pay you back, you break his legs, or take his sons and daughters as slaves. Today we have reduced the violence. Now companies ruin credit, get a Sheriff to evict someone from a house foreclosure, harass you with phone calls .. it's a less violence but it's still a form of it.
This violence is also the origin of money (and debt). A conqueror takes a country. That leader needs to pay his army (they are expensive). So you take the area you took and they can only pay taxes with coins; your coins specifically. Only soldiers have those coins, so you leave a garrison that gets paid from the debt you put the people in.
Before the US destroyed Libya, it had the highest GDP in Africa and no debt to the WMF. Today, the "rebels" the US imported are now in debt to the WMF and the people no longer have free electricity or education.