Oil prices surged, stocks dropped and investors flocked to safe havens like gold on Friday after tensions between Israel and Iran escalated, stoking concerns of a broader conflict in the region.

That scenario now appears alarmingly close. On the evening of June 12th, Israel launched dozens of air strikes on Iranian military and nuclear sites. The attack threatens to inflame the Gulf, which pumps a third of the world’s oil. Brent crude, the global benchmark, rose by 8% on June 13th, to $74 a barrel (see chart). How high might it now go?