But Major General Amir Eshel, the commander of the Israeli Air Force, says that the added challenge is not insurmountable.

Still, the completion of this sale, which was originally arranged in 2007 but delayed by international outcry before being effectively greenlit with the advent of the nuclear agreement, speaks to the source of some concerns that traditional American allies have regarding the growth of Iranian power in the Middle East.

What’s more, the S-300 transfer is not an isolated incident, but is part of a larger expansion of cooperation between Tehran and Moscow, which has included mutual evasion of international sanctions, mutual support for the dictatorship of Bashar al-Assad in Syria, and just last week, joint naval maneuvers off the northern coast of Iran.

Radio Free Europe / Radio Liberty reported on Tuesday that Iranian Foreign Minister Mohammad Javad Zarif was meeting with his Russian counterpart Sergei Lavrov. The two held a joint press conference in Moscow in which they indicated that they would seize upon the implementation of the nuclear agreement to expand economic and military relations.

RFE/RL added that this meeting of foreign ministers followed upon a summit of emerging economies last month in which Iranian President Hassan Rouhani and Russian President Vladimir Putin met as well. They were joined by officials from several other countries including China, thus pointing to concerns among some Western analysts about the emergence of a broad coalition of Asian powers as a force of opposition to Western interests.

China has also shown interest in expanded military and trade relations with Iran, as with its own joint naval exercises in the Persian Gulf.

Meanwhile, Iran appears to be using the leverage provided by its widening inclusion in the world community in order to try to force reconciliation of certain regional conflicts in Iran’s favor. Iranian and Russian officials recently discussed Tehran’s proposal for an end to hostilities in Syria, ahead of plans to present the same proposal to the UN. But this proposal is certain to presuppose the continued rule of Assad, a prospect that has previously been rejected by the US and much of Europe.

Tehran may be pursuing a similar course in Yemen, urging Saudi Arabia and its allies to withdraw from hostilities even as Iran continues to provide material support to the Houthi rebels who ousted President Abd Rabu Mansour Hadi early this year.

In part because of the apparent one-sidedness of Iranian proposals for reconciliation, Saudi Arabia, the United Arab Emirates, and Bahrain have all dismissed the notion of meeting and talking with representatives of the Islamic Republic. Other members of the Gulf Cooperation Council have been less definitive, but the Saudi’s have expressed concern about letting their guard down at a time when Iran’s regional intrusions have garnered unprecedented opposition from its rivals.

Gulf News quotes one senior GCC official as saying, “Dialogue with Iran would be a waste of time and effort in light of [Tehran’s] hostile policy. [It] would weaken the decisive position the GCC countries have adopted under the leadership of Saudi Arabia.”

This decisiveness has been partly attributed to uncertainty about the extent to which the US is prepared to act in the interests of its traditional Arab allies. The Obama administration met with the GCC last month to attempt to sell it on the nuclear agreement while leaving the impression that the US would curtail Iranian power if it became a threat. But the Saudis and other Arab leaders continue to voice skepticism.

While most Arab concerns about a lack of US action are related to broad matters of policy, critics also periodically highlight individual failures to take decisive action against Iran’s aggressive or illegal activities. Many American critics of the nuclear deal, for instance, have made reference to perceived neglect of American citizens being held prisoner in Tehran.

Thus far, Amir Hekmati, Pastor Saeed Abedini, and Washington Post correspondent Jason Rezaian all remain in prison. Hekmati was originally condemned to death before that sentence was replaced with a jail term, and Rezaian has yet to be sentenced for the vaguely-defined national security crimes of which he is accused.

But British critics have an arguably more serious failure to call attention to in light of a report by the Daily Mail regarded the execution of an Afghan translator who had worked with the British military. The translator was attempting to reach the West after fleeing threats from the Taliban, but he was reportedly captured in Iran, tortured, and murdered either by Iranian authorities or by Shiite militias. The Daily Mail adds that four other translators are believed to have suffered the same fate, and that anyone who has worked with Western powers in the past is likely to be killed by the Iranians or their regional allies.

Also on Tuesday, an editorial in Bloomberg View highlighted the common criticism that the nuclear agreement and broader Western policies toward Iran have served to marginalize and even endanger the democratic opposition to Iran’s clerical regime. But while reiterating this perspective, the article takes the optimistic step of suggesting that President Obama could help to build as a private citizen the support that he withheld as head of state.

This would be in Obama’s interest, the article states, because the nuclear deal that he spearheaded can only succeed in the long term if the Iranian regime falls. This will require coordination among Tehran’s existing foreign and domestic opponents, especially if Iran continues to build supportive ties with other major powers in the East.