At its narrowest point, the Strait of Hormuz measures just 21 nautical miles across. Through this slender passage flows approximately 20-25% of the world’s oil supply and a significant share of global liquefied natural gas (LNG) exports. No other geographic feature has such concentrated importance for the world economy.
Geographic Position¶
The Strait of Hormuz connects the Persian Gulf to the Gulf of Oman and, from there, to the Arabian Sea and Indian Ocean. It is bounded by:
- Iran to the north, with a long coastline and numerous islands
- Oman (the Musandam Peninsula) and the United Arab Emirates to the south
- Two shipping lanes, each roughly 2 miles wide, separated by a 2-mile buffer zone
The navigable channels pass closer to the Iranian shore than the Arab side—a geographic fact with significant strategic implications.
Why Hormuz Matters¶
Oil Transit¶
The Persian Gulf contains approximately 48% of proven global oil reserves. The major producers—Saudi Arabia, Iraq, Kuwait, the UAE, and Iran—export most of their oil by tanker through Hormuz.
Daily transit volumes typically exceed 17-20 million barrels per day. The primary consumers of this oil:
- Asia: China, Japan, South Korea, and India depend heavily on Gulf oil
- Europe: Significant imports, though less dependent than Asia
- United States: Less dependent since the shale revolution, but still affected by global price dynamics
There are limited alternatives. Saudi Arabia has pipelines to the Red Sea, and the UAE has a pipeline bypassing Hormuz, but these have limited capacity and cannot replace tanker traffic.
LNG Exports¶
Qatar, the world’s largest LNG exporter until recently, ships virtually all its gas through Hormuz. Other Gulf states are expanding LNG production. Closure of the strait would devastate global gas markets.
The Iranian Position¶
Iran’s control of the northern shore gives it significant leverage:
Geographic advantages: - The main shipping lanes pass through waters Iran can easily reach with coastal missiles, mines, and fast attack boats - Iranian islands (Greater and Lesser Tunb, Abu Musa) extend its reach into the strait - The Iranian Navy and Revolutionary Guard Corps Naval Forces maintain substantial presence
Threatened closures: Iran has repeatedly threatened to close Hormuz in response to economic pressure or military attack. Whether it could sustain closure is debated, but even temporary disruption would shock global markets.
Asymmetric capabilities: Iran has invested heavily in: - Anti-ship missiles (cruise and ballistic) - Naval mines (thousands stockpiled) - Fast attack craft and swarm tactics - Submarines (including mini-submarines) - Shore-based artillery and rockets
A conventional military confrontation with the US Navy would not end well for Iran, but Tehran’s ability to inflict damage and disrupt shipping is substantial.
Strategic Scenarios¶
Temporary Disruption¶
Even short-term disruption—from military conflict, accidents, or political crisis—would:
- Spike oil prices immediately (the “fear premium”)
- Strain global oil reserves
- Force expensive rerouting of tankers
- Destabilize energy-dependent economies
The 2019 attacks on tankers near Hormuz, attributed to Iran, demonstrated the market’s sensitivity. Oil prices jumped despite minimal actual supply disruption.
Extended Closure¶
A sustained closure would constitute a global economic crisis:
- Oil prices would reach unprecedented levels
- Asian economies would face energy emergencies
- Global recession would likely follow
- Military intervention would become probable
For this reason, the United States maintains significant naval forces in the region and has repeatedly stated that keeping Hormuz open is a vital interest.
Mine Warfare¶
Mining the strait is perhaps the most likely Iranian asymmetric option. Mines are cheap, difficult to clear, and psychologically powerful—insurers will not cover tankers transiting mined waters, halting traffic even if the mines pose limited actual danger.
The US maintains minesweeping capabilities, but clearing operations in contested waters would be challenging and time-consuming.
The American Military Presence¶
The United States Fifth Fleet, headquartered in Bahrain, is specifically tasked with maintaining freedom of navigation in the Gulf and Hormuz:
- Aircraft carrier strike groups rotate through the region
- Guided missile destroyers and cruisers provide air defense and strike capability
- Minesweepers and patrol craft address asymmetric threats
- Air bases in Qatar, UAE, and elsewhere extend reach
This presence reflects the judgment, consistent since the Carter Doctrine (1980), that the Persian Gulf is a vital American interest warranting military commitment.
Regional Dynamics¶
Arab Gulf States¶
Saudi Arabia, the UAE, Kuwait, and others depend on Hormuz for their economic survival—oil exports fund their governments and societies. They have invested in:
- Alternative pipeline routes (limited capacity)
- Strategic oil reserves
- Hosting American and allied military forces
- Their own naval and air capabilities
The UAE, in particular, has built a pipeline bypassing Hormuz to the port of Fujairah, providing some insurance against closure.
Oman¶
Oman occupies a unique position. The Musandam Peninsula gives it sovereignty over the southern shore of the strait, yet Oman has maintained cordial relations with Iran. This neutrality has made Muscat a back-channel for diplomacy.
China and Asian Importers¶
China receives approximately 40% of its oil through Hormuz. This dependence creates a strategic vulnerability that Beijing is keenly aware of—and one reason China has pursued overland energy routes through Central Asia, pipelines from Russia, and investments in alternative suppliers.
Japan and South Korea, with virtually no domestic oil production, are even more dependent and have aligned closely with American security guarantees.
Historical Incidents¶
The Tanker War (1980s)¶
During the Iran-Iraq War, both sides attacked tankers in the Gulf. The “Tanker War” phase (1984-88) saw:
- Over 400 ships attacked
- US naval escorts for reflagged Kuwaiti tankers (“Operation Earnest Will”)
- The USS Stark struck by Iraqi missiles (37 dead)
- The USS Vincennes shooting down Iran Air Flight 655 (290 dead)
- Direct US-Iran naval clashes
Post-2019 Tensions¶
Following US withdrawal from the Iran nuclear deal (JCPOA) and reimposition of sanctions:
- Tankers were attacked near Hormuz (attributed to Iran)
- Iran seized a British tanker
- A US drone was shot down over the strait
- Tensions repeatedly approached the brink of open conflict
Future Scenarios¶
Nuclear Iran¶
An Iran with nuclear weapons would alter the Hormuz calculus. Tehran might calculate that nuclear deterrence provides cover for more aggressive actions in the strait, while adversaries might be more reluctant to respond militarily.
Energy Transition¶
As the world shifts away from fossil fuels, Hormuz’s importance will gradually decline. However, the transition will take decades, and during that period, oil will remain critical. Natural gas may actually increase in importance as a “bridge fuel.”
Regional Realignment¶
The Abraham Accords and shifting alignments in the Middle East could reduce tensions—or could isolate Iran further, making it more likely to use Hormuz as leverage.
Conclusion¶
The Strait of Hormuz illustrates a fundamental geopolitical truth: chokepoints matter. The physical configuration of the earth’s surface creates points where traffic must concentrate, and those who control such points possess leverage disproportionate to their other resources.
For all the talk of a “flat world” enabled by technology, the barrel of oil that powers the global economy still must pass through a 21-mile gap between Iran and Arabia. Until that fundamental fact changes, Hormuz will remain one of the most strategically significant places on earth.