Traffic through the Strait of Hormuz collapsed, US President Donald Trump has been urging allies to help reopen the narrow stretch of water.
For the first time since the conflict began, traffic through the strait reportedly dropped from over a hundred vessels per day to zero. No ships passed through due to the blockade by Iran.
That moment highlights just how critical this waterway is—and raises a key question: why can Iran effectively control a strait it does not actually own?
The Strait of Hormuz is one of the most important oil transit routes in the world. Although it is only about 30 to 50 kilometers wide, roughly 20 million barrels of oil pass through it every day—close to 20 percent of global supply.
The geography explains its importance. The strait sits between some of the world’s largest energy exporters, including Saudi Arabia, Iran, Iraq and the United Arab Emirates. For many of them, it is the main shipping route connecting the Persian Gulf to global markets.
When tensions rise in the region, oil prices usually react immediately. Disruptions in this narrow passage can send shockwaves across the global energy market.
Technically, the Strait of Hormuz includes international waters. But Iran’s geography gives it a powerful advantage.
Iran controls the entire northern coastline of the strait. Under the rules of the United Nations, coastal states can claim territorial seas extending 12 nautical miles (about 22 kilometers) from their shores.
The strait is relatively narrow, which allows Iran to exert significant influence over maritime traffic.
Importantly, Iran does not need to impose a full blockade to disrupt shipping. Even limited military capabilities—such as fast attack boats, drones, or naval mines—can create enough risk to deter commercial vessels.
In such situations, the real barrier often becomes economic rather than military. Insurance premiums surge, and shipping companies simply avoid the route.
The effects of disruption are global, but not evenly distributed.
Asia is particularly vulnerable because around 80 percent of the oil passing through the strait is destined for Asian markets. Countries like Japan and South Korea rely heavily on Middle Eastern energy supplies and would feel the impact quickly.
China is also affected, though not to the extent sometimes claimed. Estimates suggest oil shipments through Hormuz account for only about 6.6 percent of China’s total energy consumption.
For the United States, the impact is more immediate politically. Rising oil prices translate quickly into higher gasoline prices, which American voters tend to notice.
With midterm elections approaching, surging fuel costs could create pressure for the White House. Stabilizing the Strait of Hormuz would help calm global oil markets and ease domestic economic concerns.
Yet reopening the strait is far from guaranteed. Iran has signaled a strong willingness to retaliate, and tensions in the region remain high.
As long as instability persists around this narrow passage, the consequences will extend far beyond the Middle East.
When a single strait carries one-fifth of the world’s oil, its disruption becomes a global problem.
Reporter: Xie Hongzhou
Cameraman: Xie Hongzhou
Video: Guo Hongda
Poster: Lai Meiya
