Key Point: Iran has been seeking to establish a degree of asymmetric deterrence by independently investing in short-range and medium-range ballistic missiles.

The debate about the development of Iranian missile capabilities started the very day after the adoption of UNSC Resolution 2231, which endorsed the Iran nuclear deal or the Joint Comprehensive Plan of Action (JCPOA). While the United States and the European parties argued that the resolution limited any activity in relation to the development of Iranian ballistic missiles, Iran would invoke Paragraph 3 of the annex B of the resolution, arguing that the restrictions were only on ballistic missiles that were capable of carrying nuclear warheads. This disagreement on interpreting the provisions of the resolution led U.S. President Donald Trump to call the JCPOA a “bad deal” before even entering the While House, and was purportedly one of the reasons why he finally withdrew from it in May 2018. Meanwhile, Iran’s response to the reimposition of sanctions within the framework of the U.S. “maximum pressure campaign” has been that Tehran will not negotiate over its missile capabilities.

The Islamic Republic of Iran is approaching its forty-first anniversary while seeing the United States as its archfoe over all the four past decades. Ideological differences; bitter experiences such as the 1953 Iranian coup d'état led by the United States, which resulted in the overthrow of the first democratically elected government of Mohammad Mosadeq; and the later overthrown Shah’s dependence on the United States have all shaped the mentality of the Iranian policymakers and have persuaded Iran to act against U.S. policies in the Middle East. Forty years of hostile relations between the two countries, as well as the attempt of two most recent U.S. presidents to impose the toughest sanctions in history on Iran have brought the Iranian officials to the conclusion that the United States seeks to change the Iranian regime through either a real or a soft war or both.

In addition, Iran has found itself encircled by the U.S.’ longtime allies and friends in the region, which has become more chaotic and violent since the U.S. invasions of Afghanistan and Iraq. These perceptions among the Iranian leadership at micro level, and the Middle East’s changed security environment at macro level, have brought Iran to the conclusion that its security and survival in the turbulent Middle East can be ensured only through strengthening its deterrence power. Thus, deterrence forms the cornerstone of Iran's defensive policy. Iran's deterrence is made up of three intertwined components that compliment each other and have been able to secure the Islamic Republic over the past forty years.

The first and foremost deterrence component in the Islamic Republic of Iran's defense policy is to strengthen its military capabilities based on missile defense. Iran has been banned from purchasing any conventional weapons since the early years after the 1979 revolution, while U.S. allies in the region, including Saudi Arabia and the United Arab Emirates, have been adding to their military power by purchasing billions of dollars in advanced military weapons like fighters and bombers. For instance, Saudi Arabia signed an arms deal with the United States in May 2017 which is worth $350 billion over ten years. At the same time, Iran is surrounded by three nuclear powers, namely India, Pakistan and Israel, each with sizeable nuclear arsenals. Israel, the U.S. regional ally that has declared Iran as its arch foe also possesses ballistic missiles that are capable of carrying nuclear warheads. Moreover, Iran is encircled by dozens of U.S. military bases all around its territorial borders, from major air bases in Qatar, Bahrain and the UAE to Incirlik Air Base in Turkey. Advanced U.S. warships sailing in the waters around Iran, especially in the Persian Gulf, have also tightened the siege on the country.

In such circumstances, Iran has been seeking to establish a degree of asymmetric deterrence by independently investing in short-range and medium-range ballistic missiles. Iran's military capabilities cannot match those of the United States and its allies in the region. Unlike Iran’s regional rivals, Tehran does not have advanced U.S.-made fighters, but its mid-range missiles can target U.S. allies in the region. According to the 2019 US Department of State's Missile Defense Review, Iran's medium-range ballistic missiles can reach the Mediterranean sea and its anti-ship, short-range missiles can threaten U.S. and allies’ naval vessels in the Persian Gulf. The increasing number, precision, range, and lethality of Iran's missiles indicate the seriousness of the Iranian government’s determination to strengthen its defensive capabilities as one of the most important pillars of its national security.

According to reliable media reports and what Iranian authorities have stated so far, an array of short and medium-range ballistic missiles has been manufactured and successfully tested in Iran: Sejjil are the first long-range, two-stage, solid-fueled ballistic missiles in Iran with an operational range of nearly 2,000 km; Shahab, which are manufactured in three types of Shahab 1, 2, and 3 are the most famous generation of Iranian-made missiles; Shahab 1 with a range of 300km, Shahab 2 with a range of 500 km, and Shahab 3 with a range of 1.300-1,700 km are liquid-fueled missiles; Khalij Fars (Persian Gulf) missiles are supersonic ballistic missiles that can carry a warhead of up to 500 kg and could strike 90-100 tons warships; Ghadr-110 missiles are one of other generation of ballistic missiles with a range of more than 2,000 kilometers. Ghadar-110 is the improved model of the Shahab 3 missiles. Khorramshahr is another Iranian missile with a range of more than 2,000 kilometers. It is without fins and capable of carrying up to 1800 kg warheads; Ghiam-1 is the first without fins ballistic missile with a range of 800 km and carries a 746 kg warhead.

Experience and history have made Iran determined to develop its missile systems. The eight-year war with Iraq from 1981 to 1989 put very bitter memories in the minds of Iranian politicians. While Saddam Hussein was bombing Iranian cities with a variety of missiles and modern warplanes, Iran did not have missile deterrence power and every country refused to sell missiles to Iran. During more than five stages of Iraqi missile attacks against densely populated Iranian cities, known as the War on the Cities, most of Iran's major cities, including the capital Tehran, were heavily targeted and more than a quarter of Tehran's population had to flee the city and seek refuge in surrounding villages and towns.

The second component of Iran's deterrence is the formation of a kind of alliance system in the region which Iranian officials call “the Axis of Resistance.” Having found itself surrounded by U.S. regional allies and military bases in the Middle East, Iran has tried to prevent a negative shift in the balance of power and to ensure its security by providing material and moral support to the Axis of Resistance. Iran believes that because it is not a member of any formal security and military alliance and it is not supported by any major military power, it has to strengthen its deterrence power by developing its influence in Lebanon, Iraq and Syria. In this context, it becomes relevant to realize that one of the major factors that held back the United States from a military response to Iran's shooting down of one of its advanced drone over the Persian Gulf back in June was its fear of reaction from Iran's regional allies.

Iran's extensive influence in Lebanon, Syria, Iraq and Yemen by its support for the Axis of Resistance has, in turn, reinforced Iran's missile defense power. This influence signals to the United States and Iran’s regional opponents that it has the potential to use those countries’ soil to station its missile. Israel has repeatedly targeted alleged Iranian positions on Syrian and Iraqi soil over the past two years, claiming that its strikes are an attempt to prevent the deployment of Iranian missiles in those areas. Israeli officials have recently claimed that Iran is deploying its missiles in Yemen to target Israeli soil from there. Prime Minister Benjamin Netanyahu has also claimed that Iran is planning to increase the number of its missiles in Lebanon to 130,000. He has also warned that Iran is deploying missiles in Iraq and Syria. Iran has never responded to such Israeli claims, but its officials have constantly talked of the necessity of being fully prepared for a possible war by the United States and its allies.

The third component that has made Iran's deterrence policy relatively successful is its advantageous geographical status at the strategic Strait of Hormuz, which explicitly suggests its key role in maintaining security of the flow of energy through the Persian Gulf. Relying on this geopolitical advantage, Iranian President Hassan Rouhani has already implicitly threatened to block oil shipments through the Hormuz Strait. Rouhani said on July 21 that "if Iran's oil is not exported, no regional country’s oil will be exported." More than 30 percent of the world's oil passes through the Strait of Hormuz. Therefore, any disruption to this important waterway would mean a serious blow to the world economy.