Iran does not like Turkey supporting Syrian rebels but does little beyond complain about Turkey and Iran disagreeing about what is happening in Syria. Iran is intent on maintaining good relations with the Turks, who have been a formidable (and usually a victorious) foe for centuries. This strategy is based on fear, reflected in a recent Turkish opinion poll that showed 54 percent of Turks approved Turkey developing nuclear weapons if Iran does. To make matters worse, Turkey has joined with the Sunni Arabs to rebuild the old (pre-1918 when the Ottoman Turk empire collapsed) coalition opposing Shia Iran. Back in Ottoman times Turkey was the undisputed leader but now must share that with Saudi Arabia. Much to Iran's discomfort the Turks are making this unnatural marriage (the Turks and Arabs never really got along) work.
In Syria Iranian advisors have prevailed over more bloody minded Syrian leaders who wanted to kill a lot more protestors, in order to terrorize all the others. The Iranian advisors speak from experience and it is Iranian cash that keeps the Syrian government running in the face of economic sanctions. Iran loses a lot if the pro-democracy rebellion in Syria succeeds. At that point a loyal ally turns into another bitter Arab enemy. Worse, it becomes much harder to support the Hezbollah militia that runs southern Lebanon. Hezbollah, armed with over 40,000 Iranian rockets, is the only weapon Iran has to use against Israel if Israel tries to bomb Iranian nuclear weapons facilities. While Hezbollah would lose another war with Israel (like they did in 2006 when they accidentally started one), Hezbollah would also lose most of its rockets and other Iranian weapons. Without Syria replacing all those rockets would take a long time and might be impossible. For this reason Hezbollah is supplying men (as trainers, technicians, and, in a few cases, fighters) and weapons to Syria. Throughout all this Syrian and Hezbollah personnel in Syria are under orders to keep their heads down. The Lebanese and Iranians wear Syrian uniforms as needed, unobtrusive civilian clothes otherwise. Foreign media are kept at a distance. But a growing number of Syrians fleeing the country have seen the foreigners in action and recognized where they were from and what they were doing.
Iran needs also Hezbollah to support a worldwide network of Iranian spies and terrorists. Since Hezbollah is Lebanese they have an easier time connecting with the worldwide network of Lebanese expatriates (many of whom fled during the 1975-90 civil war that helped create Hezbollah). Iran uses this network as a support force for Iranian agents. If Hezbollah is weakened or destroyed, so is much of Iran's foreign espionage and terror capability. Some overseas efforts would not be hurt, like those closer to home (in Afghanistan, Yemen, and Arabia).
Iran is not too worried about an Israeli air strike because the Israelis are already waging a covert war against Iran's nuclear weapons program. This has been going on for several years and is doing an increasing amount of damage.
Iran is also using rather quiet moves to increase its influence in Iraq. One critical operation is to get a pro-Iranian Iraqi cleric appointed (by a council of senior clerics) the chief Shia cleric for Iraq. Because most Shia clerics, especially the elite ones, go to elite religious schools in Iran, the Iranians have a good idea how all the Iraqi candidates think. Using the same tools (bribes, favors, blackmail, whatever it takes) employed to ensnare Iraqi politicians, the Iranians are trying to persuade the senior Iraqi clerics to pick the right guy when the aging and sickly incumbent (81 year old Grand Ayatollah Ali al Sistani) finally dies.
In Afghanistan Iran is using more money than guns to influence the media and public opinion. Western Afghanistan has, in the past, often been a part of Iran and Afghans are willing to take what they can get from the Iranians. If the Iranians want to pay the local media to say nasty things about the Afghan government or the Americans, or get local people to stage demonstrations for those causes, there is not a lot of resistance. Iran has always played the long game, and the Afghans (including the Afghan government) respect that.
The U.S. believes that there is enough spare capacity in the world oil supply to replace what is lost by cutting off Iranian exports. Starting June 28, the world is supposed to stop buying Iranian oil, as part of a sanctions program to get Iran to stop developing nuclear weapons. Iranian oil shipments are already down 14 percent. But two of Iran's major oil buyers, China and India, refuse to abide by the sanctions. China is doing it largely for economic reasons. By defying the sanctions China has more leverage and is able to get a lower price for Iranian oil. India, on the other hand, wants to keep good relations with Iran in order to gain access to Central Asian (including Afghanistan) trade routes. In addition, "sticking it to the West" is still popular in India (which was an anti-West "neutral" during the Cold War). Despite Chinese and Indian support, it looks like there will be a ban on insurance for ships trading with Iran. This will force China and India to provide insurance, which will increase their costs a bit.
The sanctions are having a growing impact. Shortages of foreign currency mean many foreign goods cannot be imported. General mismanagement of the economy by the corrupt government means inflation is now running at a high rate (north of 20 percent a year). Most Iranians are feeling the pain but not the corrupt officials that are responsible for it.
