Since ISIL (al Qaeda in Iraq and the Levant) took control of the Iraqi city of Mosul on June 9th 2014 Iran has abandoned the unwritten agreement it has had with the Shia dominated Iraqi government since 2008. Back in 2008 the Iraqi government used Iraqi soldiers and police to crush the Iran backed Mahdi Army militia, and several similar organizations. These were private armies run by Shia religious leaders, usually with considerable (cash, trainers, weapons) support from Iran. These groups wanted to establish a Shia religious dictatorship in Iraq similar to what had been running Iran (not very efficiently) since the late 1980s. The 2008 Iraqi crackdown indicated that the Iran backed militias were not strong enough to defend themselves, much less force the creation of a religious dictatorship. Iran had already been convinced that most Iraqi Shia did not want a religious dictatorship. The 2008 crackdown showed that it was prudent for Iran to back off and bide its time.
Now the time has come. The Shia politicians running Iraq allowed their corrupt behavior to cloud their judgment and that led to the collapse of many army and police units in the last month. Meanwhile these same politicians had allowed the defeated Shia militias to continue existing, as long as the military side of these organizations was deemphasized. While this rule was generally observed, since 2008 many of these militiamen were sent to Iran for further military training. This was no secret to the Iraqi government but everyone knew that if you kept quiet about it the Iranians would not cause trouble. Iran also cooperated by pulling most of their Quds Force trainers and operatives (including those from Lebanese Hezbollah Unit 3800) out of Iraq after 2008. Many of those trainers and advisors are now back, particularly those from Unit 3800. These trainers and advisors make a big difference when you have a lot of eager and armed volunteers but not much combat training or experience. Quds and Hezbollah are quickly getting these militias back into shape for combat.
The Lebanese Unit 3800 is modeled on the Iranian Quds Force. Both are full time operations, composed of men trained to spread the Islamic revolution outside Iran. The core operatives of the Quds force comprises only a few thousand people. Unit 3800 is much smaller, with only a few hundred members. But many of these operatives are highly educated, most speak foreign languages, and all are Islamic radicals. They are on a mission from God to convert the world to Shia Islam, and the rule of Shia clergy.
The Quds Force has been around since the 1980s, and their biggest success has been in Lebanon, where they helped local Shia (who comprise about a third of the population) form the Hezbollah organization. After 2003 Quds Force helped Hezbollah create Unit 3800 to help train Islamic radical Shia militias in Iraq. These militias were frequently used to attack American troops as well as Sunni Islamic terrorists. Unit 3800 personnel were easier to hide since they were Arabs while most of the Quds people are ethnic Iranian (Indo-European) and have a hard time passing for Arabs,
The Quds Force, being a much larger organization than Unit 3800, also has a lot more responsibilities. Thus Quds has eight departments, each assigned to a different part of the world. While the one that works in the Palestine/Lebanon/Jordan area have been the most successful, the other departments have been hard at it for over two decades. Quds Force also helped Hezbollah create Unit 1800, whose main function is to help train Palestinian Islamic terrorists.
The Western Directorate has established a recruiting and fund raising network in Western nations. Many recruits are brought back to Iran for training, while Shia migrants are encouraged to donate money, and services, to Quds Force operations. Because many of these operations are considered terrorist operations, Quds Force is banned in many Western nations.
The Iraq Department long maintained an army of anti-Saddam fighters in exile (in Iran) as well as running an intelligence operation inside Iraq. After the coalition toppled Saddam in 2003, Quds Force moved people, money and weapons into Iraq, to form pro-Iranian political forces and militias. These are the men withdrawn after 2008 and who are back now.
The South Asia Department (Afghanistan, Pakistan, and India) was active in aiding Afghan Shia who were being persecuted by the Taliban (a Sunni operation) and al Qaeda (a very Sunni operation). Quds has also been caught operating in Pakistan, where Sunni terrorists have been attacking Shia for decades.
The Turkey Department has been active encouraging Shia Kurds to commit terrorist acts.
The North Africa Department has an operation in Sudan that functions in the open despite the Sunni conservatives who run the country. This department was caught providing weapons to the Sunni Islamic Courts militia in Somalia in 2007 and later providing support for the even more radical al Shabaab.
The Arabian Department supports terrorist groups that exist in all the Persian Gulf Arab countries. The Arab Sunni governments in these nations does not appreciate Iran’s support for this sort of thing.
The Central Asian Department supports Shia and Sunni terrorists in countries that used to be part of the Soviet Union. So does al Qaeda, but the Quds operation has been more discreet.
Back in Iran, Quds is believed to provide safe houses (or house arrest) for al Qaeda and other Sunni Islamic terrorist leaders, even though al Qaeda has taken part in many atrocities against Shia outside Iran. However, the "enemy of my enemy is my friend." Actually, there is an ongoing dispute in the Iranian government over the al Qaeda issue. But the Iranian leadership is more a federation than a dictatorship, so Quds can keep being nice to al Qaeda as long as not too many factions get mad at Quds.
The Iranian leadership, despite their radical sounding pronouncements, have actually been quite cautious. This is in line with ancient Iranian custom. Most of the Hezbollah violence in Lebanon was at the behest of Lebanese. The same pattern has occurred elsewhere. The Quds guys usually counsel restraint, although in Iraq there has been more enthusiasm for violence. Iraq is a special case, as several hundred thousand Iranians died fighting Saddam in the 1980s, and Iranians have not forgotten. While Saddam is dead and gone many of his followers are in ISIL and for the Iranians the debt is still not paid.