Yesterday I linked to a StrategyPage article about Russia in Syria. Today I found this article about the problems Iran is facing in Syria and elsewhere. Here's an excerpt.
Iran points out that ISIL (Islamic State in Iraq and the Levant) and all the other Islamic terrorist rebels in Syria are the result of the Saudis and other Gulf oil states' generous supporting Islamic radicals worldwide for decades. Iran is able to keep these Sunni terrorists out of Iran and the West has managed to contain them as well. So the Sunni Islamic terrorists mainly kill other Sunnis in Moslem countries, as well as a lot of Shia. This gives Iran a legitimate excuse to get involved in nations where there are significant Shia minorities and having provided this aid for so long Iran has become the indisputable leader of the Shia world.
While Iran is technically part of the international anti-ISIL coalition it often uses rather than attacks ISIL because this group of Sunni radicals is more of a threat to Sunnis than to Shia. You can see this in Syria where ISIL is less concerned about overthrowing the Assads and more into expanding the “caliphate” they have created out of eastern Syria and western Iraq since 2014. So while the Arabs and the Americans bomb ISIL Iran and their ally Russia concentrate on the other Sunni rebels (most of them Islamic terrorists affiliated with al Qaeda). ISIL have been at war with these other Sunni Islamic terrorists for two years now and the pro-Assad forces will step aside to allow the Sunni fanatics to kill each other and then go after the winner. ISIL and many other Sunnis Islamic terrorists were aware of this early on and had worked out some informal, and quite fragile, alliances. Everyone knew this was temporary because once the Assads were gone the victorious Sunni Islamic terrorist groups, who believe democracy is heresy, would fight it out for supremacy.
Iran exploits that mentality (which is less common among Shia) and, along with Russia, says they are in Syria to fight Islamic terrorists but in reality leave ISIL alone and concentrate on rebel groups that are the biggest threat to the Assads. Meanwhile it is to Iran’s advantage that ISIL hold the attention of the West and the Arabs. Iran is fighting ISIL, but mainly in Iraq, where Sunni Islamic terrorists have long focused their attacks on Shia civilians. Since the Shia are a majority in Iraq Iran becomes even more popular there as Iran backed militias and other military assistance plays a crucial role in driving ISIL (and eventually all Sunni Islamic terrorists) out of the country. Iranians speak openly (especially inside of Iran) of how well they have exploited their enemies and duped [them] into fight[ing] for Iran instead of against Iran.
Iranian media (and the government) is less interested in publicizing how the Gulf Arabs, led by Saudi Arabia have driven the price of oil so low, and kept it there, that Iran has been greatly weakened. This is a defeat the Iranians are quietly seeking a solution for. The Saudis say their oil price war is directed at American frackers but savvy Iranians (especially those with kin in America) know that is a lie or a delusion on the part of the Saudis. The American oil industry has proved itself very resilient and innovative since the Americans invented the oil business in the 19th century. The frackers, as expected, shut down much of their production as it got unprofitable but are hibernating, not dying. Iranians believe they are the real target of the Saudi oil price campaign because low oil prices, which went from a 2014 peak of $120 a barrel (159 liters) to less than $40 now, keeps Iran weak. At the same time the math indicates that the Saudis cannot keep it up for more than another five or ten years. At that point the Saudis run out of cash reserves and borrowing ability. The Saudis are betting that Iran will crack first while the Iranians believe they can outlast the Saudis. Place your bets. Inside Saudi Arabia the media openly boasts of this particular victory over the hated Iranians.
There's more at the link. Highly recommended reading, particularly because Iran is one of the nations the USA is most likely to face in a shooting war if anything goes wrong.