The U.S.-Israel war against Iran isn’t only reshaping security and the balance of power in the Middle East. Its stakes are also high for China.
For more than a decade Iran has been a pillar of China’s global strategy. Iran supplied China with discounted energy, served as a node in the Belt and Road Initiative and challenged U.S. influence in the Middle East. Now the China-Iran partnership is under serious pressure.
According to the Foundation for Defense of Democracies, China buys roughly 90% of Iran’s exported oil, helping keep the Iranian economy afloat despite Western sanctions. Iran has at times supplied 20% of China’s imported crude, about 1.6 million barrels a day. War-related disruptions strike directly at China’s energy security: As much as 45% of China’s oil imports pass through the Strait of Hormuz.
Buying oil from Iran was a strategic decision for China. With Iran facing heavy sanctions, Chinese refiners bought its oil at steep discounts of $8 to $14 a barrel. China frequently paid in yuan, advancing Beijing’s long-term effort to weaken the U.S. dollar in global energy markets.
In 2021 Beijing and Tehran signed a 25-year strategic partnership worth an estimated $400 billion, covering infrastructure, energy and transportation. Much of that investment was tied to the Belt and Road Initiative, Beijing’s effort to build a global network of ports, railways and energy corridors linking Asia, Europe, Africa and the Middle East while expanding China’s political influence. Iran sits at the geographic crossroads of that network.
The war is also exposing China’s military cooperation with Tehran. Last year the U.S. imposed sanctions on Chinese and Iranian entities that supplied materials used in Iran’s ballistic-missile program, including chemicals required to produce rocket fuel. Analysts have reported that Iran obtained enough material from Chinese suppliers to produce hundreds of ballistic missiles. Investigative reporting has also identified Iranian cargo ships leaving Chinese ports associated with the export of rocket-fuel chemicals. Iran has lately sought to acquire Chinese supersonic antiship cruise missiles capable of threatening U.S. naval forces in the Persian Gulf.
This cooperation matters directly for American national security. It strengthens one of the most hostile regimes in the Middle East while giving China an opportunity to test the credibility of its military technology, though not without risk.
Battlefield performance carries geopolitical consequences. Israeli fighters destroyed more than 60 Syrian aircraft supplied by the Soviet Union in 1982 without losing a single plane. Soviet air defenses that had been widely exported suddenly appeared weak, and Moscow’s reputation as an arms supplier suffered.
China faces a similar risk. For decades Beijing has marketed its weapons systems as alternatives to Western equipment. If Iranian defenses influenced by Chinese technology prove ineffective against U.S. and Israeli forces, countries considering Chinese weapons will take notice.
The conflict highlights another vulnerability: China, which imports roughly three-fourths of the oil it consumes, depends heavily on maritime supply routes. If the U.S. and its allies can disrupt energy flows in the Middle East during a regional conflict, Chinese planners must consider how their supply chains would fare during a crisis involving Taiwan.
The implications extend to the Western Hemisphere. In the past two decades China has invested heavily in Latin America and the Caribbean, financing ports, energy infrastructure and telecommunications networks. Beijing has invested billions in Venezuela’s oil sector, which helped sustain Nicolás Maduro’s regime while enlarging China’s strategic footprint in the region.
For years Beijing expanded its influence while assuming the U.S. lacked the will to challenge aggressive regimes or disrupt China’s geopolitical partnerships. The war with Iran suggests otherwise.
China invested heavily in Tehran, bought its oil, supplied technology, and helped Iran circumvent sanctions. Yet when conflict arrived Beijing largely limited its response to diplomatic statements. That reality will be noticed in capitals across the developing world where governments have been courted by China’s offers of “strategic partnership.” Partnership implies support, not distance, when pressure arrives
The broader lesson is one that has shaped international politics for centuries: Strength shapes strategy. The Trump administration’s National Security Strategy emphasized restoring American military and economic strength to counter Beijing’s expansion. The war with Iran shows that idea being carried out.
China built part of its global strategy on Iran. That strategy is now being tested.
Mr. Spencer is chairman of war studies at the Madison Policy Forum.