The Strait of Hormuz is a narrow waterway that lies between Iran and Oman. This 21 mile-wide passage supports 20% of the world’s oil supply. A closure of this waterway could send the global economy into a tailspin. In recent months, several oil tankers have been seized, attacked and harassed. These oil tankers — and this narrow water passage — are at the center of the conflict between the US and Iran. It's a conflict that spans decades and has the potential to escalate in one of the world’s most important oil chokepoints.