After a temporary, three-year reprieve, Iran sanctions will soon be back in place thanks to US President Donald Trump’s decision to withdraw from the Iran nuclear deal. Many of the new restrictions will come into force in November. It is to be expected that most (if not all) economic actors will be forced to comply or risk being locked out of the US financial system. Considering that oil is Iran’s primary export commodity and that it is an important source of revenue, the resumption of sanctions will have a profoundly negative impact on the country. But sanctions will also affect states that currently import oil from Iran, forcing them to adapt in order to ensure their continued energy security; and this will in turn benefit other oil-exporting countries that can pick up the slack. Moreover, the new restrictions will create opportunities for cooperation, and competition, between major powers.