To find buyers for all this extra oil, roughly equal to the extra output produced by the US shale revolution, Iran will have to compete fiercely not only with Saudi Arabia, but also with Iraq, Kazakhstan, Russia, and other low-cost producers. All of these countries are also determined to restore their output to previous peak levels and should be able to pump more oil than they did in the 1970s and 1980s by exploiting new production technologies pioneered in the US.