After the Islamic revolution in Iran in 1979, the main directions of Iran's foreign policy were determined by the specific character of state's power building based on Shiite clergy, which took root in politics. Traditional Islamic values served as the main ideological justification for Iran’s foreign policy. The external factor played a significant and sometimes decisive role in Iran’s policy [Arab-Iranian Relations, 1988, p. 3–18, 73–103]. Iranian leaders have made their bet on Lebanon since the early 1980s. Taking advantage of the Israeli occupation of Southern Lebanon and 1982 war, Iran sent about 3,000 fighters from the elite units of the Islamic Revolutionary Guard Corps (IRGC) through Syria to the country. Their task was to support the Shiite movement in Lebanon [Akhmedov, 2001]. In an effort to realize the idea of creating an Islamic republic in the image and likeness of Iran, the leaders of Iran clearly understood that it was impossible to achieve without establishing their complete control over the Shiite community of the country. The solution of this problem had a special resonance under conditions of struggle for Lebanon. By the early 1980s the Amal² organization has won a strong position in the Lebanese Shiite community. Its leadership (N. Berry) enlisted the support of Damascus and did not want to lose its influence on the Shiite community, reorienting itself to the interests of Iran. The Iranian leadership launched a powerful propaganda campaign against N. Berry and provided significant financial and ideological support to his deputy H. Mousavi, a graduate of Tehran University and a zealous supporter of the ideas of Ayatollah Khomeini. In summer 1982, H. Moussavi accused N. Berry of betraying interests of the Lebanese Shiites. He announced his withdrawal from Amal and created a new Shiite organization (Islamic Amal). Later, this organization became one of the main instruments of Iranian foreign policy in Lebanon. The ambiguous attitude of the Islamic authorities of Tehran towards Amal looks quite justified.

After the Syrian military redeployment in Lebanon in 1976, Iran's oppositions groups passed through training courses in the camps of the Shiite movement Amal, controlled by Damascus [Shireen, 1996]. An Israeli invasion in Lebanon (1982), advanced into the regions of Khalid and the western Beka'a (valley), where the Amal and al-Da'awa³ detachments were operating, showed the lack of new organizational forms and counteracts methods to struggle with Tel Aviv. This was the reason for the split of Amal. Members of “al-Daawa” and other Islamic organizations decided to dissolve themselves. In June 1982, at the organizational congress, in which representatives from various regions of Lebanon took part, a decision was made to create a new Hezbollah organization. One of its leaders was Abbas Moussavi. The fighting backbone made up of an Islamic youth cell, that decided to act as an independent Islamic group in the fight against Israeli troops. H. Nasrullah himself, who was 22 at the time, did not take part in the work of this youth cell. In 1985, at a meeting of pro-Iranian organizations in Lebanon, the leaders of Hezbollah, Islamic Amal and other Lebanese groups adopted long-term program guidelines. Their essence was to strengthen the positions of Iran and Hezbollah in Lebanon. The task was to liberate the occupied south of Lebanon, war with Israel up to its complete destruction, fight against Western, primarily American influence in Lebanon. In this regard, at the end of 1987, the leaders of Iran reoriented themselves. They made a bet in the leadership of Hezbollah on Sheikh Subhi Tufayli. He was originally from the village of Brital (Beka'a Valley). S. Tufayli was considered in Tehran as a politician, loyal to Iran. After the withdrawal of Israeli troops from the most of Lebanese territory in 1985, Hezbollah, with the active support of the Islamic Revolution's Guards Corp (IRGC), began to build its own arsenal.

Hezbollah's strengthening

The strengthening of Hezbollah, especially its position in the areas of traditional influence of Amal, soon led to increased rivalry between two organizations, which in the second half of the 1980's took the form of violent armed clashes, along with the aggravation of Palestinian civil strife in Lebanon. Damascus intervention was able to stop the bloody clashes between Amal and Hezbollah, which took on a particularly violent character in 1988. Because of the so-called Taif Accords of 1989, Syria managed to prevent the disarmament of Hezbollah, leaving it as the only Lebanese organization with military infrastructure. Damascus was able to exercise control over the supply of weapons to Hezbollah. In January 1989, “special agreements” were reached between Damascus and Tehran. Lebanese Hezbollah has rebuilt its military infrastructure and resumed operations in southern Lebanon. In 1991, Hezbollah became the leading Lebanese resistance force operating in the south of the country against the South Lebanese Army (SLA) and Israeli troops. By this time, it became clear, that the policy of creating an Islamic republic in Lebanon, similar to the Iranian one, was facing great difficulties.

In the summer of 1992, the Iranian leadership recommended that Hezbollah leaders transform organization from a purely paramilitary group into an active political force in Lebanese society. The leaders of the organization announced the rejection of sabotage and terrorist methods and somewhat reduced the level of military activity in southern Lebanon. In the fall of 1992, Hezbollah won 8 out of 128 seats in the Lebanese parliament, which allowed it, blocking with other Islamist deputies, to have from 10 to 20 % of the vote and thus to claim the role of one of the leading political forces in Lebanon [Akhmedov, 2002]. H. Nasrullah formally headed the organization in February 1992 after the death of A. Mousavi during an Israeli Air Force raid on southern Lebanon. Former Hezbollah Secretary General S. Tufayli, the leader of the “radicals”, did not join the leadership, and his supporters, who came from the Beka'a and the northern regions, lost almost all leadership positions in the organization. The regular congress of Hezbollah, held in July 1995, retained control over the leadership of the organization in the hands of H. Nasrullah and his supporters. In 1992, the combat forces of the military wing in Hezbollah were separated into an independent combat unit, not formally associated with the organization. Hezbollah preserved the organization's weapons as a serious advantage to challenge eventual changes in the region.

The total number of Hezbollah members by the beginning of the 2000s numbered over 10,000 soldiers. Over the past two decades, the activities of Hezbollah structures subordinated to the military tasks of the Islamic Resistance. Iran, together with Syria, pursued an active policy to strengthen its influence in the Middle East. This political line corresponded political developments in Lebanon. In summer, 2006 (Israeli attack on South Lebanon) Hezbollah successfully contained Israeli offence. During the toughest political crisis in Beirut (2008) that nearly broke the country on the brink of civil war, Hezbollah took power in the country and became a military political force in 2009 resisting Israeli aggression in Gaza (Palestine).

A number of important factors, which had a significant impact on its policy, determined Iran’s activities in the Middle East. Iran’s support for Hezbollah used to strengthen its influence in Lebanon as a tool to contain Israel’s aspirations. Iran was involved in the inter-Palestinian and Israeli-Palestinian conflicts. It provided international support and assistance to Palestinian Hamas [Ehteshami, Hinnebusch, 1997, p. 27–57]. In the parliamentary elections in Lebanon in August-September 2000, Hezbollah won 12 seats in parliament. Acting in such different guises, Hezbollah had hundreds and thousands of activists and supporters in Lebanon. Its secular and religious activities were an important part of the life of the Shiite community in Lebanon and provided it with a solid and long-term basis for mobilizing new loyal members and fighters from among the local population into its ranks. Over the past two decades, the Shiite bourgeoisie of Lebanon has grown stronger. It waged an active struggle for the redistribution of the existing zones of financial and economic influence, transportation routes and trade markets. The Shiite “nouveau riche” used the potential of Hezbollah to exert a beneficial influence on their economic competitors, both from among the Shiites and representatives of other faiths. In exchange for supporting the organization, they provided Hezbollah with their financial assistance.

The process of creation of Hezbollah was determined by the strong desire of the Iranian political elite to integrate into the Lebanese political life, rather than by an attempt to export the Islamic Revolution abroad. Hezbollah has always been a “problematic” organization from the point of view of the Syrian regime. In fundamental questions of Islamic faith and practice, Hezbollah was closer to Tehran, and the ideological orientation of the organization was far from the ideas of non-proletarian socialism of the ruling Syrian Ba'ath party. In addition, the tasks of Hezbollah in Lebanon did not always coincide with Damascus' plans for this country and the region as a whole. Syria had to closely monitor that Hezbollah's actions against Israel complied with the established “rules of the game”, as well as constantly monitor the activities of the organization so that it did not go beyond the Syrian interests and political plans in the region. In 1990-2000, Syria controlled Hezbollah. This control facilitated by the fact that since 1976 a 30,000-strong contingent of Syrian troops deployed in Lebanon. Damascus used Hezbollah to contain Israel, but did not want to strengthen an organization that could rival it in Lebanon. The Syrian control over the organization has been steadily lessened by the growing influence of the Islamic Republic of Iran in the Levant.

Meanwhile, Syria, as the heartland of Arab nationalism, has striven to overcome the political fragmentation of the Arab world by acting as a trigger for Arabs Unity. Hafez Al-Assad and Ruhollah Khomeini regarded their alliance as a vital tool to increase regional autonomy by diminishing foreign penetration into the Middle East. Iran’s influence on Syria increased especially after Bashar Al-Assad had come to power in June 2000. Iranian penetration into Syria peaked in 2007–2009. At that time, Iran signed a series of profitable economic contracts with the new Syrian leadership and an agreement on military cooperation that got it prolongation in 2019-2022. This allowed Iran to penetrate almost all the institutions of the Syrian state, at first in the army and security apparatus, and to start to play an increasing role in Syrian society, exerting a beneficial influence on the mentality and views of the ruling Syrian elite.

Syrian Crisis put Hezbollah in a difficult position. The unrest in Syria showed the full extent of the severity of the division of the former alliances in the region. The Syrian Crisis has become a real test for Hezbollah. The rebellion against al-Assad's regime dealted severe ideological blows to Hezbollah's ally in Tehran. Iran needed Syria for a number of reasons. Due to the efforts of Al-Assad's regime, Tehran managed to thwart the emergence of united front of the USA and its Arab allies against Iran. Damascus served as a conduit for Iranian policy in Lebanon. Iran has always viewed Damascus as an important link in the “Islamic resistance”, where Hezbollah played a leading role. As events developed in Syria, Tehran could no longer count on the previous support of Damascus to protect its interests in Lebanon. Taking into account the Syrian events, many Lebanese political forces could change their attitude towards Iran; reconsider the previous nature of their ties with Tehran [Akhmedov, 2010, p. 152-173]. Iran also feared that regime change in Syria could undermine Iranian interests in the region. Iran played a leading role in maintaining the current regime in Syria.

Since January 2012, the Iranian Central Bank opened a multi-billion dollar credit line to the Syrian authorities, which allowed them regularly pay salaries to the personnel of the Syrian armed forces, fighting against the armed opposition. At the same time, Iran sent several thousand Hezbollah soldiers, advisers and specialists from the elite al-Quds corps (IRGC's detachment), as well as Shiite militias from Iraq and Afghanistan, to assist Al-Assad's army. As the Syrian armed uprising turned into a civil war, Iran increased its military presence in Syria. In fact, Iran's politics in Syria determined by considerations of an internal order, the priority of which was the desire by any means to achieve the nuclear power status⁴. Iran considered Syria as a “trump card” in a larger geopolitical game. Tehran viewed Damascus as an important springboard in spreading its influence in the region [Akhmedov, 2010, p. 134–153]. In the context of the Syrian crisis, Hezbollah built its strategy around a 5-year plan. According to this plan, Hezbollah, on the eve of the events, began to create weapons depots on the Syrian territory and to organize secret Islamic resistance units. At the same time, Hezbollah did not count on a prolonged armed conflict in Syria. The organization was afraid that a long war in Syria could affect its position in Lebanon. Hezbollah had no desire to incur future human and material losses in Syria. Regard those perceptions the leadership of Hezbollah adopted a plan to build an outwardly independent structure in Syria. This militia troops had to be under control of the Shur'a Council and subordinate directly to the Secretary General of Hezbollah H. Nasrullah. By this Hezbollah sought to expand its influences far beyond Lebanon and to strengthen its position in Iraq and Yemen.