A Thorn in Tehran’s Side: Afghanistan’s Multifaceted Threat to Iranian Security

Afghanistan's ongoing instability and Taliban machinations are major concerns for Tehran

A Taliban fighter stands guard at the Afghanistan-Iran border. Afghanistan presents a series of strategic challenges for Tehran. Source

Thousands gathered in Kerman, Iran on January 3 to commemorate the anniversary of the death anniversary of General Qasam Soleimani. The former head of the Islamic Revolutionary Guard Corps (IRGC) Quds Force who led a protracted campaign against Sunni extremists across the Middle East, Soleimani had been killed in a US airstrike in Baghdad, Iraq four years prior. At around 3:00 PM, a suicide bomber detonated a blast that tore through a procession near the cemetery where Soleimani was buried. 15 minutes later, another suicide bomber triggered an explosion aimed at the fleeing crowd and emergency workers on the scene. Over 90 people were killed and nearly 300 injured in what is now the deadliest terror attack in Iran since the 1979 Islamic revolution. Responsibility for the horrific attack was later claimed by the Islamic State Khorasan Province (ISKP), a terror group based in neighboring Afghanistan.

Afghanistan represents a persistent threat to Iran’s internal security on a number of fronts including terrorism and insurgency, criminal activity, and even water. These factors combined present a very dangerous outlook for Iran moving forward with little solution on the horizon

Locations of the twin suicide bombings on January 3. Source

The two suicide bombers of the Kerman attack. Source

How Afghan instability impacts Iran

Iran shares a 945-kilometer (587-mile) border with that includes three official border crossings in the eastern Iranian provinces of Razavi Khorasan, South Khorasan, and Sistan and Baluchestan. Most of this border area is a rugged, arid desert, making the border generally porous despite Tehran’s construction of partial barriers. For this reason, Iran is highly exposed to various threats emanating from Afghanistan, which has been essentially a failed state for over forty years.

Terrorism and Insurgency:

The ISKP is Iran’s primary security threat from Afghanistan. Formed as part of the broader Islamic State (IS) movement in 2014, the Sunni-Salafist group is directly opposed to Iran’s Shia regime, viewing it as both an ideological and military rival. Iran has a substantial history of fighting Islamic State militants internally and to its west: a 2017 attack on Tehran that killed 20 was linked to IS militants. Moreover, Iran’s Al Quds force – previously under the direction of Soleimani – has been fighting IS through its proxies in the Middle East for over a decade. Now with a substantial IS branch operating to its east in Afghanistan, Tehran faces threats from the group on practically all sides.

Including the latest attack in Kerman, the ISKP has conducted at least three successful attacks in Iran over the past 15 months and has attempted others. The group also regularly publishes propaganda in Farsi/Persian in an attempt to stoke sectarian divisions in Iran by radicalizing the country’s Sunni population. Iran is currently home to some eight million Sunni Muslims, a growing population that is comprised mostly of ethnic minorities who are regularly discriminated against both politically and economically. With Tehran increasingly fearful of its Sunni minority in recent years, these threats posed by the ISKP are even more potent.

Afghanistan serves as a transnational hub for terrorist threats to Iran. Although the Kerman attack was perpetrated by the Afghan-based ISKP, all of the identified attackers were Tajikistan nationals. In this way, the ISKP also leverages its networks in Central Asian countries to threaten Iranian security. With the ISKP’s Central Asian contingent continuing to build its capacity to conduct external operations, Iran is very likely to be targeted in future attacks.

Afghanistan’s large Baloch minority also poses a threat to Iran as the porous border region between Iran, Afghanistan, and Pakistan allows ethnic Baloch separatist and Sunni Islamist groups to move relatively freely between the three countries. In Iran, the Sunni separatist group, Jaish al-Adl poses a persistent threat to the Iranian regime and Tehran alleges that the group moves freely between the three countries. Jaish al-Adl has been waging an insurgency against Tehran since the early 2000s and in a recent attack, killed 11 Iranian police officers and soldiers in the town of Rask, Sistan Baluchistan province in December 2023. This attack came on the heels of a spate of attacks in Iran last year, and several more since 2012.

With Baloch groups  gaining strength in neighboring Pakistan, evidence indicates they are in close contact with their counterparts in Afghanistan due to their use of American weapons left by the United States after its withdrawal from Afghanistan. In this way, Afghanistan continues to be a haven for various transnational terror and extremist groups that threaten Iranian security

Predominantly Baloch territories in Afghanistan, Iran and Pakistan (in pink). Source

Transnational crime and illegal migration:

The porous border between Iran and Afghanistan has allowed for the trafficking of people, drugs, and weapons between the two countries. Afghanistan has long been the center of the narcotics trade in the region, and Iran is both a transit point and final destination for drugs (including heroin) from Afghanistan. Moreover, Iran has one of the largest methamphetamine markets in western Asia and Afghanistan is among the world’s top producers of the drug. In 2022, Iranian forces seized 1,118 kg of crystal meth being smuggled from Afghanistan into northwest Iran’s Khorasan province: this was the largest meth seizure in Iran’s history. Although the Taliban has clamped down on opium cultivation, smugglers continue to traffic large quantities of other drugs into Iran by various means, including via slingshot. Such activities have frequently resulted in armed clashes between smugglers and security forces at the Afghan-Iranian the border.

Iran is also home to some three million undocumented refugees from Afghanistan, many of whom have been brought there by illicit human trafficking rings. In addition to security concerns, this has had a major socioeconomic impact across much of Iran. Moreover, Iran’s internal corruption problems prevent it from effectively combatting illicit cross-border activity as Iranian officials have often been found to be complicit in colluding with trafficking syndicates.

Flow of drugs from Afghanistan to Iran and the region at large. Source

Fraught relations with the Taliban amid worsening water crisis

Tehran has historically had troubled relations with the Taliban from the early days of the Afghan group’s rise to prominence. When the Taliban captured the northern Afghan city of Mazer-e-Sharif in August 1998, they killed 10 Iranian diplomats and one Iranian journalist at the Iranian consulate there before massacring thousands of Afghan Shia in the city in just a few days. Tehran deployed some 200,000 troops to the border and threatened to invade Afghanistan in response: this set the stage for decades of enmity between the Taliban and Tehran. Although the US occupation of Afghanistan eventually brought the two sides closer in later years, tensions remain with violent border clashes erupting in May of last year with water being a key underlying factor.

Water scarcity is a growing concern for Tehran and the Afghan Taliban are threatening to exacerbate the issue. In 2023, Iranian officials warned that over one million hectares of Iranian lands are becoming inhospitable due to persistent drought. Iran is currently in its fourth year of a severe drought that is threatening the livelihoods and security of millions of its citizens, resulting in mass protests across the country and especially in the Afghan border province of Sistan and Baluchistan.

Last year’s border clashes between Iran and Taliban forces came amid a longstanding dispute over a water sharing agreement between the two countries. Specifically, previous Afghan governments have constructed dams along the Helmand River that restrict the flow of water into Iran and the Taliban plans to build more: Tehran claims that this violates a 1973 treaty between the two countries while the Taliban dispute this. Iran claims that it only receives four percent of the water it is supposed to receive from the Helmand and similar Taliban projects have given rise to similar concerns in neighboring Pakistan, Uzbekistan, and Turkmenistan. Although the latest border row was quickly deescalated, the potentially catastrophic impact this could have on Iran’s basic security needs is likely to result in further tensions moving forward. These tensions could impede meaningful engagement between Tehran and the Taliban, limiting the kind of security cooperation between the two parties needed to find a solution to Iran’s long list of security grievances with its neighbour to the east.

Conclusion

Iran’s engagement with the Afghan Taliban comes as it has no other good options to deal with the major threats emanating from Afghanistan. The Taliban are likely willing to engage with Tehran as a means of enhancing their legitimacy and combatting the ISKP. Moreover, the economic challenges faced by both countries have caused them to recent enter talks to boost annual trade up to $10 billion in the coming years. However, the Taliban’s continued and potentially existential threat to Iran’s water security will likely keep relations between the two strained moving forward.

The Afghan Taliban have proven the be an unreliable neighbor not only to Iran, but also to Pakistan, which also suffers from major security issues emanating from Afghanistan. For this reason, Afghanistan will likely remain a major strategic vulnerability for Tehran in the foreseeable future.