The Diplomat author Mercy Kuo regularly engages subject-matter experts, policy practitioners, and strategic thinkers across the globe for their diverse insights into U.S. Asia policy. This conversation with Dr. Can Kasapoğlu – nonresident senior fellow at the Hudson Institute and formerly Eisenhower fellow at the NATO Defense College in Italy and visiting scholar at the NATO Cooperative Cyber Defense Center of Excellence in Estonia – is the 487th in “The Trans-Pacific View Insight Series.”
Compare and contrast China-Iran defense cooperation before and after the 12-Day War between Israel and Iran in June 2025.
The most significant shift in Chinese-Iranian defense dynamics following the 12-Day War stems from a third actor: the Russian Federation. On the very day that Israel bombarded Iranian targets, no Russian Su-35 air-superiority fighters were scrambling in quick reaction alert role, nor were the Russian S400 air defense batteries engaging Israeli air raids. Iran couldn’t even compensate for the losses of its air defense architecture from last year’s Israeli military action. All in all, Russia has proven to be an unreliable arms supplier to the Islamic Republic.
This is why China has tremendous potential. If Beijing chooses to fill the void left by the Russians, it could bring about a significant shift. While we currently only have speculations from various international news outlets about the possible delivery of Chinese air defenses, such as HQ-9s, to Iran. This claim has not been confirmed via open-source intelligence. However, the potential that China can realize in this scenario is substantial and could lead to critical outcomes.
Identify key factors behind Beijing’s calculus in positioning China as a major defense partner for Iran.
It remains to be seen whether Beijing will seize the moment or not. Until recently, the Sino-Israeli economic transactions and investment projects marked the chief predicament that stopped closer military relations with Iran. Besides, China is a major drone warfare systems exporter to the Gulf Arab nations and runs critical ballistic missile projects with the Kingdom of Saudi Arabia. All these factors contributed to the limited Chinese engagement in arming Iran.
Nonetheless, with the recent fluctuations in the Middle East, we have seen tensions in the Sino- Israeli relations. Moreover, China observed that prolonged conflicts in Europe and the Middle East, particularly when occurring simultaneously, have kept the American military’s prowess and the United States’ defense industrial output busy in a distant corner of the world, away from the Indo-Pacific theater. This is a lucrative temptation for the Chinese political-military elites.
Examine how China-Iran defense cooperation could impact China-Russia relations.
We cannot jump to the conclusion that China will overall replace Russia in strategic Iranian sectors. Put simply, we lack sufficient indicators that presage such an eventuality.
In a hypothetical scenario in which China replaces Russia in the Iranian weapons market, I do not see a harsh reaction from the Putin regime. Iran is not a primary arms client of Moscow. Besides, Russian arms exports have been expectedly decreasing due to the stumbling invasion in Ukraine. The Chinese rise in Iran would be an internal power dynamic within the hostile CRINK [China, Russia, Iran, North Korea] axis.
What types of air defense and missile capabilities would Tehran seek to acquire from Beijing?
The Islamic Republic has a huge problem: it cannot control its airspace. It remains very vulnerable to any prospects of a second round in the 12-Day War.
This is why, in an ideal world, Iran would seek to secure a substantial package, including high-end fighter aircraft and high-end air defenses, from China.
The HQ-9 SAM system would be a good candidate. The Chinese air defense system would need anti-stealth sensor capabilities to stand a chance against Israel’s air power, such as the YLC-8B and the JY-27A.
In the combat aerial platform segment, the J-10C has established a strong reputation since the 2025 skirmishes between Pakistan and India.
Iran’s interest in securing Chinese anti-ship missiles, such as the YJ-12, could pose a significant risk. The transfer of such critical Chinese technology to Iran’s proxies could prove very dangerous and is a factor that should not be overlooked.
Last, following the depletion of the Iranian missile arsenal due to the 12-Day War, China can loom large as a provider of missile rocket motor fuel components to Iran.
Assess the strategic implications of China-Iran defense ties for the United States and Israel.
This depends on the content of potential arms deals, delivery timelines, and China’s diplomatic willingness to carry on despite the snapback sanctions.
If everything goes as the Iranian elite planned, and if Tehran can land the entire shopping cart, it can give Israel some trouble – or at least make another 12-Day War costlier in the risk calculations and more expensive.
As for the United States, things are complicated. Prolonged conflicts in the Middle East and Europe slowly attrit American military capabilities, due to the scarcity of potent allies with decisive military capabilities or the will to employ them. An Iran-China defense partnership would introduce a notable attrition trend in that sense.
