The Strait of Hormuz is the waterway that connects the Gulf of Oman and the Persian Gulf. It is the only waterway that connects the oil-rich nations in the Middle East with the Indian Ocean, which is vital for maritime traffic, as seen below:
The Strait of Hormuz is incredibly important to the international oil market, and remains the most important oil chokepoint around the globe. Each day, 17 tankers travel through the Strait carrying some 18 million barrels of oil, which equates to around 20 per cent of oil traded worldwide, and 35% of all oil transported across water. Because of the limited onshore infrastructure in the Middle East, by way of lack of pipelines, around 80 per cent of oil leaving the Persian Gulf travels through the Strait of Hormuz. This demonstrates the importance of the Strait to international oil markets.
The Strait itself is only 21 miles wide at its narrowest point, between the Omani Musandam Peninsula at Oman and Iran. There are 8 small islands within the Strait of Hormuz, seven of which are controlled solely by Iran, and the last one by the United Arab Emirates. Iran has maintained a military presence on the seven islands since the 1970’s. The Iranian Navy has access to the open sea through the ports at Bandar Abbas, Büshehr, and Chah Bahar and with its de facto control of the seven islands in the Strait; Iran has been able to maintain a significant influence in matters concerning the waterway and in the region more general.
To control the flow of traffic through the Strait, vessels follow a traffic separation scheme (TSS), which helps to reduce collisions. There are two shipping lanes, one for vessels moving one way, and one for vessels moving in the opposite direction. The lanes are each two miles wide, and are separated by a 2 mile wide gap in between. This leaves relatively little room for ships to manoeuvre within the TSS zone.
In order to pass through the Strait of Hormuz, vessels must transverse the international waters of both Oman and Iran. This gives Iran some strategic advantage and often the Iranian elect will threaten to close the Strait over international relations disputes, like the topical question regarding Iran’s nuclear programme. Disputes occur regularly, and most often with the United States, given that the Strait is so important to them (currently), because the state of the world economy depends heavily upon the flow of oil from the oil rich nations in the Middle East to the rest of the world. There is a common fear that Iran could hypothetically close the Strait of Hormuz and cause mass disruption in oil markets and hence the global economy, but research has shown that whilst this may be the case only slightly, Iran doesn’t possess the military or technical ability to do so, and the various economic, political and military forces present in the region today make any real disruption unlikely.