The Newsweek report emphasized the fact that the trade fair’s announcement unsurprisingly anticipated participation by government delegates and business leaders from countries like Iran and Russia, which supported the government of Bashar al-Assad throughout its conflict with a diverse array of rebels including moderate, pro-democracy groups in addition to Sunni militants like the Islamic State of Iraq and the Levant. In a somewhat less expected turn of events, though, the announcement also made reference to some countries that had backed the opposition to the Assad dictatorship.

Representatives of either the government or the private sector in such countries as France, Germany, Spain, Jordan, Bahrain, and the United Arab Emirates are all expected to be in attendance at the trade fair, despite having supported the pro-democracy rebellion through much of the civil war. However, the announcement made no mention of the United States, in what could be an example of Syria being used as leverage in the growing conflict between the US and the Islamic Republic of Iran.

The Syrian Civil War served to promote divisions between Iran and several of its actual or prospective allies, even as it apparently helped Iran to draw closer to Russia after Russian air support began to support Iranian operations on the ground in 2015. Now that the war is apparently winding down, there are emerging opportunities for the Assad government to court investment from some of its former opponents while Iran strives to expand its regional influence by mending fences that were erected over divergent interests in Syria.

One of these opportunities was highlighted earlier in the week when it was reported that the chief of staff of the Iranian armed forces had traveled to the Ankara for three days of talks with the Turkish government. Those talks reportedly focused on the conclusion of the Syrian Civil War and specifically the future of the last major rebel stronghold, Idlib. Full details of those talks are not yet widely available, but on Thursday, Reuters reported that the administration of Turkish President Recep Tayyip Erdogan announced that it would be bolstering military cooperation with the Islamic Republic.

It remains to be seen what implications this agreement will have for the mainly Sunni rebels that Turkey had been supporting in Syria. But it is presumably bad news for the Kurdish rebel groups that Turkey never supported but instead regarded as a threat to its own national security. The United States, by contrast, continues to support the Kurdish YPG along with other groups that remain as bulwarks against Iranian interests in Syria and the region as a whole.

This situation partially illustrates why Iran’s outreach to other pro-rebel powers cannot extend to the US. Assuming that Turkey and others have written off the rebel cause as a loss, it is now possible for them to find places where their subsequent interests align with those of Iran. And at least in the case of Turkey and its distrust of Kurdish forces, this overlap threatens to add an ally to Iran’s efforts to undermine American interests in the Middle East.

Of course, more obvious examples of these efforts take the form of Iran’s relationship with various regional terrorist groups. These relationships were also strained by the Syrian Civil War, and that strain stands to be relaxed as the war winds down. On one hand, Iran’s Lebanese proxy force, Hezbollah, was empowered by its contribution to the Iranian war effort, which gave the terrorist organization a potentially permanent foothold in the Golan Heights, across the border with Israel. But on the other hand, fellow anti-Israeli terrorist group Hamas broke away from Iran when it found itself split between the Shiite Islamic Republic and the Sunni Muslim Brotherhood over the Syria issue.

US Treasury Department official Daniel Glaser explained this situation in an interview with Majalla Magazine this week and explained that Hamas and Iran have since been able to patch things up. “I suppose,” he said, “the parties found that what bound them together — namely, their desire to wreak havoc in the region — outweighed the issues that were keeping them apart.”

But Glaser’s remarks also called attention to the fact that there is a counter-trend to Iran’s efforts to expand its influence while isolating the US. Recognizing the growing entrenchment of that influence in Syria, Iraq, and elsewhere, various Arab States and their traditional adversaries in Israel are increasingly coming together strategically to counter Tehran’s regional strategy. Reuters also reported on Wednesday that Saudi Arabia and some of its allies were overlooking sectarian differences with Iraqi leaders like Muqtada al-Sadr, for the sake of their mutual interest in preventing Iran from dominating other regional governments.

Naturally, these opponents of Iranian influence represent opportunities for the United States to better exert its own influence as it develops a strategy to counter Iran and its uncertain roster of allies during and after the wind-down of the Syrian Civil War.