Comment by addicted

There are both hard and soft reasons for this.

Hard reason: Oil was traded in U.S. dollars. This was basically built off America’s status as the only open superpower and its military strength.

Soft reasons: U.S. political stability (yeah, it’s hard to understand that now after the past decade, but generally the U.S. has been extremely politically stable with Presidents largely maintaining their predecessors foreign policy even if they didn’t agree with them), US company culture which is much cleaner than the rest of the world (American companies are far less likely to bribe, for example), and strong financial institutions like the independent Fed and the publishing of reliable and open data.