People always seem to forget why the USD has value. It isn't that there's something inherently awesome about the USD. It is that the US since the 19th century has always been the highest energy extraction economy in the world.
US extracted up to 70% of global oil in the 1910s.
For reference all of OPEC combined is around 37%.
US also had the technology to turn oil into work i.e. mechanical machinery and cars.
It has nothing to do with good governance or democracy or what not. It all has to do with offering energy to high tech low energy countries, offering tech to low tech high energy countries, and most of all, keeping high tech high energy countries down.
The science behind this.
86% of economic growth comes from increasing aggregate efficiency, as per Rifkind.
It's basically how efficiently you generate energy and turn it into a final product.
Yes, it was the US at the forefront of the 2nd Industrial Revolution (centralised electricity, oil, cars, telephones)
But you still need a stable and predictable investment environment (aka good governance) so that those trillions of investments can be made, because they will take years to payoff.