Ria Reddy, Katherine Wells, Alexandra Braverman, Andie Parry, Ben Rezaei, Carolyn Moorman, George Ekmekjian, Faris Almaari, and Brian Carter



Information Cutoff 2:00 pm ET

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Iran continued to threaten US bases and forces, likely to try to discourage a potential US or Israeli strike on Iranian nuclear facilities amid US threats to strike these facilities. Iranian armed forces-run Defa Press published a piece on April 2 claiming that Iran "certainly has sufficient weapons" to attack Diego Garcia Island. The United States has recently increased its military presence at Diego Garcia Island. The piece stated that US Air Force and Navy "strategic assets" and "4000 US soldiers" at Diego Garcia would be "at risk of complete destruction" if the United States attacked Iran. There are normally roughly 400 US military personnel and 2,000 civilian contractors at Diego Garcia. The article outlined the following options for an Iranian attack on US assets at Diego Garcia.

• Missile and drone attack: Defa Press stated that Iran could conduct a drone attack "using advanced Shahed 136 drones." Iran unveiled the Shahed-136B drone in September 2024 and claimed it has a range of 4000 kilometers (km). The original Shahed-136 drone has a maximum speed of 185 km per hour, which means it would take about 20 hours to reach Diego Garcia from the southernmost city in Iran. Iran previously launched about 170 drones in their April 2024 attack on Israel, none of which entered Israeli airspace, in part because the drone’s slow speed enabled allied aircraft to intercept and destroy the drones. The drones launched from Iran would have taken roughly nine hours to reach Israel, though Israel had the benefit of a plethora of Israeli and allied land-based aircraft available to intercept drones. Defa Press also stated that Iran could use ballistic and cruise missiles, including Khorramshahr ballistic missiles, at "close range" to Diego Garcia. Iran's stockpile of medium-range missiles and ability to manufacture some advanced ballistic missiles have been severely depleted following the April and October 2024 Israeli airstrikes on Iran, but Iran would presumably expend a large proportion of its remaining stockpile in the event of a strike on its nuclear facilities. Iran would need to significantly decrease the payload of its drones and missiles or otherwise alter the weight of the drones and missiles themselves to launch a land-based attack with sufficient range to hit Diego Garcia.

• Naval drone and missile attack launched from surface vessels: Defa Press also threatened that Iran could hit targets in the Indian Ocean using surface vessels, presumably its drone carriers and others, to launch cruise missiles and drones. This would—in theory—allow Iranian ships to get closer to Diego Garcia. Such vessels lack the necessary countermeasures to seriously defend themselves against US naval action, however. 

Key Takeaways:

• Iran continued to threaten US bases and forces, likely to try to discourage a potential US or Israeli strike on Iranian nuclear facilities amid US threats to strike these facilities. Iranian media said that Iran could attack Diego Garcia using very long-range one-way attack drones or by using a naval surface combatant to launch drones and cruise missiles.

• Hezbollah may be using networks abroad to help it reconstitute its military capabilities in Lebanon. Spanish security forces detained three individuals residing in Barcelona, Spain, on April 1 on suspicion of purchasing drone components on behalf of Hezbollah. These individuals are likely part of a larger, Spain-based Hezbollah cell that has been procuring drone parts through European front companies for Hezbollah since at least 2015.

• The Syrian Democratic Forces (SDF) and interim government appear to be reaching a series of agreements to redistribute territory after signing a comprehensive ceasefire on March 10. 

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