the MR. X INTERVIEWS Volume 1 by Luke Gromen (pg. 19)

To oversimplify, the petrodollar system meant that the Americans got 10-15 percent of the world’s oil for free, every single day, and in return, the Emerging Markets got US production capabilities, access to US consumer markets (into which EMs indirectly supplied the lending capital), and a great big pile of US Treasury bonds.