Why Isn’t Russia Defending Iran?

Iran is suffering blow after blow, and Russia, its most powerful supporter, is apparently not prepared to do much of anything about it.

Not long ago, backing the West’s least-favorite power in the Middle East had its uses. In prosecuting his war of attrition in Ukraine, Vladimir Putin has made confrontation with the West the organizing principle of his foreign policy. In that context, edging closer to Iran and its partners in the “Axis of Resistance” made sense.

Tehran was also an important supplier: It delivered Shahed drones for Russian use in Ukraine at a moment when these were particularly crucial to Moscow’s war-fighting capacity. Then came the October 7 Hamas attack on Israel, followed by Israel’s brutal war in Gaza. Leaning into pro-Palestinian and anti-Western sentiment allowed Russia to score points with global public opinion.

But dynamics that initially seemed to benefit Russia quickly became a strategic headache. First, Israel devastated Iran’s partners Hamas and Hezbollah; then, in April and October 2024, Iran attacked Israel directly with strikes that yielded only minimal damage, suggesting that Iran’s missile capabilities were not all that formidable. Israel retaliated, impairing Iran’s missile production and air defenses, including its Russian-made S-300 missile systems. Suddenly, Iran looked weak, and Russia had a choice: It could shore up its Middle Eastern ally, or it could cut its losses in a troubled region.

That Moscow could not or would not intervene decisively on behalf of its anti-Western partners in the Middle East became obvious in December 2024, when Syrian rebels ousted Bashar al-Assad, Russia’s longtime ally. Iran and Russia continued to cooperate in areas such as electronic warfare and satellite development, and they even signed a strategic-partnership treaty in January. But Russia declined to give Iran the support it would have needed—say, advanced fighter jets or sophisticated air defenses—to deter or better defend itself against further Israeli attacks.

[Read: ‘This war is not helping us’]

The truth is that Russia has always had limits as to how far it would go in supporting Iran. The Kremlin’s obsessive anti-Western agenda elevated the Islamic Republic’s importance as a partner, but Putin still has other interests in the region—a long-standing, if complicated, relationship with Israel and a need to coordinate with OPEC on oil prices, for instance—and so remained mindful of Israeli and Gulf State red lines when it came to defense cooperation with Iran. What’s more, Russia was never going to risk military entanglement on behalf of its partner, especially not while it has had its hands full closer to home.

Finally, Russia may no longer have much appetite for cooperating with Western states in curbing the spread of nuclear weapons, but it has never wanted Iran to cross the nuclear threshold. The Kremlin takes American warnings on this score seriously and has sought to avoid U.S. military action against Iran. And it has never wished for Iran to acquire the global status that nuclear weapons would confer—among other reasons, because Moscow knows that it would lose leverage over a nuclear Iran.

Russia stands to gain some advantages from a protracted war between Iran and Israel. The fighting would torpedo President Donald Trump’s attempts to broker a nuclear deal with Iran—making the United States look weak and highlighting its inability to keep Israel on a leash. Oil prices would stay elevated, especially if Iran were to close the Strait of Hormuz. This would relieve some pressure on Russia’s state finances. U.S. missile interceptors—and world attention—would be diverted from Ukraine to the Middle East. Sure, Iran would have to stop sending Russia weapons for an indefinite period. But Russia has already succeeded in localizing the production of Iranian-designed drones and sources the components from elsewhere.

Still, Iran’s humiliation at the hands of a U.S. ally can hardly please Russia’s leaders. Israel has already claimed freedom of movement in the skies over Iran. Russia may also worry that a long war in Iran could destabilize the South Caucasus (Armenia, Azerbaijan, and Georgia), where Russia has interests but for which it has had precious little bandwidth during the war in Ukraine. Nor would Moscow welcome unrest that hastens the end of the Iranian regime.

A cornered Iran could also lash out, leave the Nuclear Non-Proliferation Treaty, or dash for the bomb, laying bare the limits of Moscow’s leverage over Tehran. Russia would probably like to avoid having Iran go nuclear—but it would also prefer not to see the U.S. sweep in with military action that further weakens Iran.

[Read: What Trump knew about the attack against Iran]

On Saturday, Putin congratulated Trump on his birthday and offered to support U.S. efforts to negotiate with Iran (he had made a similar offer in early March). Ever since the inauguration, Moscow has been signaling its appetite to work with Washington on geopolitical dossiers—in part to stall on a Ukraine cease-fire. Iran presents a rare opportunity for Putin to return to the stage of great-power diplomacy by negotiating an issue of global consequence. The question is: What can Russia bring to the table?

A defenseless Iran will not respond well to Russian sticks, and in any case, Moscow is unlikely to take a punitive approach to Tehran. Russia may not have shown up as Iran’s knight in shining armor, but the two countries are still partners, and they are fundamentally united in an anti-Western agenda. Russia also has few meaningful carrots to offer Iran at this point and will be cautious about providing military equipment in a moment when Israel is systematically destroying it. And Putin is not someone who likes to openly side with what appears to be the losing party.

Russia can potentially play a practical role in a future agreement, having offered to remove Iran’s highly enriched uranium and convert it into civilian-reactor fuel for Tehran. But Russia’s technical schemes cannot bridge what is a fundamental political divide between a U.S. administration that insists on zero enrichment and an Iran that views such a demand as a call to surrender.

Strategically isolated and acutely vulnerable, Iran will be even more distrustful of the United States than it was before Israel’s attack, and it will want Russia involved for at least the appearance of balance. But Russia has little influence over the outcome of the war, Iran’s next steps, or Washington’s decision as to whether it will engage militarily.

When it comes to shaping events far from Russia’s borders, Moscow is only so interested and only so able, particularly given its deep investment in the war in Ukraine. Having anti-Western partners in the Middle East serves its purpose. But no one should hold their breath waiting for Russia to come to the rescue of Iran.