The Strait of Hormuz is a critical shipping passageway which sees roughly 20 percent of world oil demand pass through it. By blocking the Strait and restricting oil tankers from moving out into the Arabian Sea, Iran would effectively be disrupting the world economy, causing oil prices to spike. Just threatening to close the Strait typically sees increases of $5 to $10 dollars in a day, according to energy analyst Daniel Yergin.
Many energy experts cast doubt in Iran’s actual ability to close the Strait. Not only is the Strait some 30 miles wide, requiring a huge number of ships to close it, but the act of closing the Strait would cause a global reaction. Western countries aren’t the only ones that depend on the oil moving through the Strait. China has also recently become consumers of Persian Gulf oil. The United States and China would both find the blocking of the Strait unacceptable, and cooperative action would surely quickly move to break the blockade. The US Navy’s Fifth Fleet is in charge of maintaining freedom of movement in the area, and could respond with military force at the first moments of blockade.
Finally, according to Yergin, blocking the Strait simply wouldn’t make sense for Iran. Iran exports its own oil through the Strait, which “generates about $80 billion in earnings and about 60 percent of its budget.” With sanctions on Iran already seeing its currency losing 80 percent of its value to the dollar, the ability for Iran to weather the loss of its export earnings does not bode well for a prolonged blockade of world oil resources.
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