As of June 23, 2025, the simmering tensions between Iran and the United States have boiled over, with Iran launching a series of retaliatory strikes in response to unprecedented U.S. attacks on its nuclear facilities. The Iranian response has been multifaceted, including missile assaults on the Al Udeid Air Base in Qatar, a parliamentary nod to potentially close the Strait of Hormuz, and the activation of proxy forces like the Houthis in Yemen. Additionally, Iran has continued its missile strikes on Israel and issued threats of cyberattacks targeting U.S. infrastructure.
U.S. intelligence agencies are currently on high alert, particularly for the threat of radiological dispersal devices, colloquially known as dirty bombs, and the ever-elusive concern about portable “suitcase” nuclear weapons. While Iran has demonstrated conventional military capabilities and some economic leverage, the specter of radiological terrorism introduces a different layer of urgency.
Despite the heightened threat environment, analysts indicate that Iran’s current responses remain firmly within conventional parameters. This analysis aims to delineate the technical realities and strategic limitations surrounding Iran’s potential use of radiological weapons, separating genuine risks from exaggerated fears.
A dirty bomb, or Radiological Dispersal Device (RDD), combines a conventional explosive with radioactive material. Upon detonation, it scatters radiation across the vicinity. Importantly, an RDD is not a nuclear weapon and cannot generate an atomic explosion.
Most RDDs are unlikely to produce sufficient radiation to cause significant health risks. The explosion itself poses a greater danger than the radiation released. Only individuals in close proximity to the blast would face serious health consequences.
Rather than being a “Weapon of Mass Destruction,” an RDD is more accurately described as a “Weapon of Mass Disruption,” designed to provoke panic and economic turmoil. Its physical damage and the spread of radiation are limited by the size of the explosive used. Unlike a nuclear bomb, which can contaminate vast areas, an RDD typically restricts its effects to a few city blocks. While some radioactive particles may drift farther, they quickly lose potency and danger with distance.
Modeling indicates that radiation from a standard dirty bomb would disperse in a cylinder approximately 30 meters high and 150 meters wide, affecting only a limited number of city blocks under typical conditions.
The actual impact of an RDD depends on several variables, including the size of the explosive, the type and quantity of radioactive material involved, the method of dispersal, and prevailing weather conditions. In many cases, a significant portion of the radioactive material may combust during the explosion, further reducing its potential health impact.
The first notable attempt at radiological terrorism occurred when Chechen separatists planted a radioactive canister in a Moscow park as a publicity stunt, which ultimately went off without a bang. Iraq also experimented with a one-ton radiological bomb in 1987 but abandoned the project when it failed to yield lethal radiation levels, underscoring the technical hurdles associated with weaponizing radioactive substances.
The notion of suitcase nukes is another frequent topic of discussion regarding nuclear terrorism threats. During the Cold War, both the United States and the Soviet Union developed small, portable nuclear weapons, but the actual existence and security status of such devices are subjects of heated debate.
In the 1950s and 1960s, the U.S. introduced the Special Atomic Demolition Munition (SADM), a device compact enough to fit into a large backpack. Approximately 300 of these were deployed, with U.S. Army and Marine Corps commandos trained to use them on demolition missions behind enemy lines.
Modern anxieties surrounding missing suitcase nukes largely stem from a 1997 assertion by former Russian national security adviser Alexander Lebed. In a 60 Minutes interview, Lebed claimed that the Russian military had lost track of over 100 out of 250 suitcase-sized nuclear bombs. However, just three days later, the Russian Ministry for Atomic Energy dismissed his assertions, stating, “We don’t know what General Lebed is talking about. No such weapons exist.” Since that time, no credible evidence has emerged to substantiate the existence of these purported lost weapons.
Experts highlight the significant technical challenges involved in creating portable nuclear devices. The lightest such weapons weighed nearly 100 pounds (45 kg) and had a limited yield of only 0.19 kiloton. Manufacturing and maintaining such a weapon demands advanced engineering and substantial financial investment. As Vahid Majidi, then-assistant director of the FBI’s Weapons of Mass Destruction Directorate, noted, “No one has been able to truly identify the existence of these devices.”
In the nearly 24 years since Lebed’s statement, no Soviet-era suitcase nukes have ever been discovered, and no terrorist group has successfully obtained or utilized one, fortunately underscoring the difficulties of transforming Cold War-era rumors into contemporary threats.
As of June 23, 2025, Iran’s retaliation has primarily unfolded along conventional lines, including missile strikes on U.S. bases like Al Udeid, renewed assaults on Israeli targets, parliamentary moves to potentially close the Strait of Hormuz, and the mobilization of proxy entities such as the Houthis. Although Iran may have access to materials suitable for radiological weapons, the technical challenges, limited effectiveness, and the risk of severe international repercussions render such utilization improbable. The Department of Homeland Security has alerted the public to potential cyberattacks and inspired violence but has reported no specific or credible radiological threat to U.S. soil. Moving forward, it is likely that Iran will continue its response through regional proxy warfare, cyber operations, economic maneuvers via the Strait of Hormuz, and missile strikes, all while remaining within the confines of conventional conflict rather than escalating into the realm of radiological or nuclear terrorism.
