From the Vital Perspective Blog - Background Briefing: Iran's Historic and Present Ties with Lebanon, Hezbollah.

The origins of Iranian involvement in Lebanon:

Iran first became involved militarily in Lebanon when a 2500-strong Iranian expeditionary force drawn from the Revolutionary Guard land army was sent to Syria in 1982 to assist in confronting Israel during the Peace in Galilee campaign.

Although the Syrians prevented actual Iranian participation in fighting, with many of the troops being returned to Iran, the remainder (1000-1500 men) stayed on to camp in the Bekaa Valley in the midst of the Shiite population. The force established a permanent military and logistic infrastructure at Camp Sheikh Abdallah in Baalbek, (which it had captured from the Lebanese Army) and at the Zabadani Camp in Syria, northeast of Damascus. In addition, command posts, field intelligence and operations units were established at Baalbek, Beirut, Zahleh and Mashgara (south Bekaa).

However the most distinctive accomplishment of the Iranians in Lebanon was their ability to cause disparate Shiite groups (which had been operating as local clan militias) to unite under one organizational umbrella called Hezbollah ("the party of Allah"), to indoctrinate their leaders with the extremist concepts of the Islamic revolution, and to train them in the military techniques and methods of the Revolutionary Guards.

Assistance by the Revolutionary Guards to Hezbollah prior to and during the present confrontation:

Iran did all it could during the present confrontation to stress its moral support for Hezbollah, as being part of "the historic struggle against the Zionist cancer and the USA". At the same time Iran strenuously denied any military involvement in the crisis. In fact, Iran was totally involved in these events.

This involvement was led by the Quds (Jerusalem) Force, an elite unit of the Revolutionary Guards. The Quds Force commanded by Qasem Suleimani is in charge of Iranian military operations and terrorist activities world-wide, and Lebanon is one of its main theaters of operations.

The Revolutionary Guard force in Lebanon is the spearhead of Iran in its campaign against Israel. It expresses an Iranian strategy that sees Lebanon as a beach-head, and so cultivates Hezbollah and its strategic abilities as a means of reacting to Israel, to wear Israel down with the ultimate aim of destroying that country, and meanwhile maintaining a balanced deterrent against it.

Over the years the Revolutionary Guards strengthened Hezbollah's military capabilities, granting it over $100 million annually. Iran also supplied the organization with varied weaponry, some of which was used by Hezbollah in the recent conflict. Some of these weapons were used independently and others required Iranian consent before use, such as the C-802 missiles...

Further Iranian assistance to Hezbollah in the recent fighting:

Iran supplied Hezbollah with intelligence about Israel.

Technical assistance in operating weapons: This assistance complemented routine basic training held in Iran at Revolutionary Guards camps and facilities. The two main camps of the Quds Force where non-Iranians are trained are the Imam Ali base in Teheran and Bahunar camp at Kharj north of Teheran. Two Hezbollah terrorists captured by the IDF related that they had been trained by the Revolutionary Guards at the Kharj base. One of them named the commander of an anti-aircraft course in 1999 as Hassan Irelo, a senior Iranian officer in charge of training.

Courses and joint exercises held in Iran for Hezbollah included anti-tank weapons (firing Sagger and Tow missiles), and anti-aircraft missiles. Special efforts were made to train in the use of strategic missiles with ranges of over 75 and 100 km, as well as drones. Revolutionary Guards officers assisted Hezbollah in launching an Iranian drone in November 2004 against Israel.

During recent years the Iranians stepped up supply of weapons to Hezbollah by air. When humanitarian supplies were flown into Iran following the earthquakes in Bam in southeast Iran (Dec 2003-Jan 2004) at least 9 return flights were used to ferry weapons to Hezbollah.

It is estimated that some recent attempts to resupply from Iran were prevented by IDF action. But the huge arsenal amassed over the years gave Hezbollah its "second wind". Iranian leaders have recently admitted publicly to supplying Hezbollah with weapons including long range rockets that threaten Israel...