Russia and Iran is a natural marriage -- each needs the other in different ways. For one, Russia needs money, badly. Iran is about to come into a lot of it, as the Iran nuclear deal is implemented, an agreement that, by the way, Russia helped put in place. Western sanctions over Russia's actions in Ukraine, and the collapse in the price of crude oil, are devastating the Russian federal budget. Iran can help alleviate this lack of cash flow by buying a whole lot of Russian weapons.
Already Moscow is shipping Iran the S-300 anti-aircraft missile system, and there is talk of Iran buying tanks from Russia to modernize its armor, which is antiquated and sorely lacking in capability. Analysts predict that if the price of oil stays in the $30 range, Russian foreign currency reserves could be depleted within two years, along with a significant devaluation of the ruble. Russia has also announced it will be assisting Iran with the development of nuclear power facilities in the near future. It is also likely that the Iranians are not driving as hard of a bargain as the Chinese when negotiating pricing with the Kremlin. Iran owes Russia for the coming sanctions relief, and is therefore negotiating from a position of weakness with Russia.
Hezbollah, Iran's proxy terrorist army in Lebanon, is now being armed by Russia as well. Russia has built large weapons depots in Syria and given Hezbollah free access in exchange for intelligence and targeting information for Russian airstrikes originating out of Latakia and other forward operating bases Moscow has constructed near rebel-held areas. For now, Hezbollah is training these weapons on the Syrian opposition; however, at some point, they will look south toward Israel.
Russia and Syria just this month announced that they signed an agreement allowing Russia to enjoy an open-ended military presence in Syria. Also announced were joint air missions where Syrian MIG-29s escorted Russian bombers as they attacked Islamic State positions. The Russian air assault on anti-Assad forces has saved the Assad regime, and therefore Moscow's footprint in the Middle East, for now. This result obviously saves Iran's influence in Syria and Lebanon, therefore allowing Iran to maintain pressure on Israel. After all, Iran's call for the destruction of the Jewish State has never really been repudiated.
Combined with Iranian influence in Baghdad, the axis of Iran, Russia, and Syria controls territory from Persia all the way to the Levant. It truly is a remarkable turn of events. The speed in which the power vacuum was filled after the withdrawal of most American troops from the region is simply stunning.
In a period of years, the Middle East may see a nuclear-armed Iran using this regional hegemony to force its will on the world. Israel could be isolated. America and NATO might have a much tougher time shaping events in this volatile area of the globe without the ability to gain a foothold, being squeezed out by possible territorial control of this new axis.