Russian military aircraft at Iran’s Shahid Nojeh air base managed to generate global media attention twice in just a few days: first when they were unexpectedly deployed there to launch air strikes on Syria, and then when they left just as unexpectedly following annoyed outbursts from Iranian Defense Minister Hossein Dehghan.

It’s still not completely clear why the Russian aircraft had to leave. Moscow tried not to make a big deal out of it, officially confirming only that its bombers had returned from Iran. Russian media cited anonymous Defense Ministry sources as saying that a “misunderstanding” had arisen between the two countries.

Iran’s reaction was more outspoken, though it did not clarify the situation. Dehghan, who had defended the Russian bombers’ presence at the airfield just a day before he announced their departure, accused Moscow of both insufficient loyalty and eagerness to toot its own horn globally at the expense of Tehran. However, the defense minister did not say whether these were the main reasons for Russia withdrawing from Shahid Nojeh. The commotion became even greater when the speaker of the Iranian Parliament, Ali Larijani, said that Russian aircraft were still using the air base.

Amid the confusion, both Russian and international experts came up with their own versions of what had happened, and many of them—both proponents and opponents of the Kremlin’s Middle East policy—blamed the West. They said that Iran had to kick out the Russian air force over concerns that their cooperation would stand in the way of Iran’s ongoing rapprochement with the West, and because Washington was concerned that the presence of Russian military aircraft in Iran ran counter to the terms of the Iran nuclear deal.

In fact, there is no evidence that Iran’s politicians, media, or society take any notice of U.S. opinion. On the contrary, they perceive such comments as proof that Iran’s cooperation with Russia is developing in the right direction, while the “hostile plans of the West” in Syria have failed.

Iranian proponents of maintaining a dialogue with the West are currently not in a position to dictate anything to the leadership of Iran: the economic reform promised by “pro-Western” President Hassan Rouhani is faltering, there is no significant progress in returning Western capital to Iran, and people understand that sanctions will not be lifted altogether in the near future.

Russia, on the other hand, recently agreed to loan Tehran $5 billion. The key players in Iran, the country’s Supreme Leader Ali Khamenei and his inner circle, believe that tensions with the United States or EU are inevitable, and that Syria—where Russia’s support is crucial for a decisive victory—is a front line of that struggle.

Finally, Iranian politicians understand that the Iran nuclear deal is very important for U.S. President Barack Obama as part of his legacy. U.S. authorities would hardly put the deal at risk over the Russian air force’s deployment in Iran, especially since Russia’s earlier move of supplying S-300 missiles to Tehran could theoretically be construed as more of a breach than the deployment of military aircraft to Shahid Nojeh.

If the West played any role in the withdrawal, it was as follows. In his statement, Dehghan accused Russia of trying to enhance its significance in the eyes of the United States to make it easier for Moscow to secure a future deal with Washington to support Russia’s own interests in Syria, which differ from those of Iran.

His accusation echoed concerns expressed by conservative Iranian media at the start of Russia’s military operation in Syria in autumn 2015 that Russia could increase its influence there “at the expense of Iran.” From that perspective, the Russian air strikes overshadowed Iran’s contribution to the fight in previous years. The conservatives asked whether their country would be able to secure a position in post-war Syria commensurate with its contribution, or whether the main gains would go to Moscow—in which case, would Moscow try to split the gains with the United States and kingdoms of the Persian Gulf?

Dehghan’s statement demonstrates that such fears have only intensified amid Russia’s loud propaganda about the success of its air force, which forced even proponents of Russia’s engagement in regional affairs to emphasize that Iran and Russia are equal partners in Syrian affairs.

Iran’s national pride rules out the prospect of handing over any part of its territory to foreign troops. Moscow may yet be able to use Iran’s airfields for refueling (this was apparently what parliamentary speaker Larijani had in mind when he mentioned the continued use of the airfield, and senior Iranian officials have expressed willingness since the aircrafts’ withdrawal to allow this), but there can be no talk of handing over the airfield for Russia’s general use: Iran’s leaders would never be able to explain such a step to the people, and would be extremely reluctant to accept it themselves.

The “misunderstanding” reported by the Russian media is most likely related to the extent and limits of permissible usage of Shahid Nojeh. It seems that while Russia wished to obtain a second Khmeimim—its air base in Syria—Tehran could not agree to such an option.

The situation was aggravated by Russian propaganda stating that Russia had effectively obtained a military base in Iran. This assertion seriously undermined the positions of those in Iran who had defended Russia’s use of the air base: Dehghan had told the Iranian Parliament in no uncertain terms that the decision on the air base’s use had been passed by the Supreme National Security Council of Iran, which does not require approval by the Iranian Parliament, because the Russian air force was only refueling its aircraft there.

Perhaps Iran’s leaders would have suppressed popular indignation and Russian heavy bombers would still be taking off from Shahid Nojeh now had it not been for Moscow and its media playing up the prospect of establishing a Russian military base in Iran. The media obtained information about alleged agreements between Moscow and Tehran that had not been discussed with the Iranian parliament, which prompted an unabated scandal.

The withdrawal of Russian aircraft from the base is neither an achievement nor a failure of Russian-Iranian diplomacy: it is simply a reflection of the two countries’ relations. Both Russia and Iran understand that their partnership in Syria is a forced step, and each of the two countries is pursuing its own agenda.

Mutual mistrust, ambitions, and fears are natural constraints that make it impossible to enter into a full-fledged alliance, but Tehran and Moscow are willing to cooperate and support each other’s efforts on an ad hoc basis.

The Shahid Nojeh episode has not resulted in any significant changes to Russian-Iranian dialogue on Syria. The balance of power on the front lines of the war there called for the Russian air force’s presence in Iran, but the aforementioned limitations made it impossible for them to stay there on a permanent basis.