Iran has recently tested its new ballistic missile, the Qasem Basir, which has reportedly forced a US aircraft carrier to maneuver to avoid it. Mohsen Rezaee, an advisor to Iran's Supreme Leader, stated on September 6 that the missile represents a "turning point in defense strategy," claiming that it caused significant distress to US naval forces.

Rezaee's comments came a day after the Islamic Revolutionary Guard Corps (IRGC) accused US warships of participating in maritime blockades and harassing vessels in the region. He asserted that the IRGC had successfully conducted a strike that forced two enemy naval ships to retreat from the conflict zone. The US Central Command (CENTCOM) confirmed on September 5 that the IRGC had launched multiple ballistic missiles targeting two naval vessels patrolling the area.

CENTCOM reported that a US aircraft carrier and a destroyer successfully evaded multiple missile attacks from Iran without any American casualties. Brandon Weichert, a geopolitical analyst in the US, noted that the CENTCOM announcement indicates that the Iranian ballistic missile posed a serious threat to the US naval fleet. He emphasized that the aircraft carrier would not have altered its flight operations unless the missile had penetrated its defense layers and posed a significant risk.

The Qasem Basir missile, which is a two-stage medium-range ballistic missile, was unveiled in May 2025 and has an estimated range of about 1,200 kilometers. It is an upgraded version of the medium-range Haj Qasem missile introduced in 2020. According to the Institute for the Study of War (ISW), the Qasem Basir is designed to incorporate lessons learned from previous retaliatory strikes in 2024, where US and Israeli missile defense systems intercepted a significant portion of incoming threats.

Experts believe that the Qasem Basir missile has undergone substantial design modifications, enhancing its maneuverability and evasion capabilities against enemy air defense systems. The missile is approximately 11 meters long, weighs 7 tons, and carries a warhead of 500 kilograms. It can reportedly reach speeds of up to 13,600 kilometers per hour during reentry and 6,200 kilometers per hour upon impact.

In 2023, Iran's then-defense minister, General Aziz Nasirzadeh, claimed that the Qasem Basir had accurately struck targets over 1,200 kilometers away without relying on GPS, even under heavy electronic jamming conditions. He emphasized that the missile's upgraded guidance system and maneuverability allow it to overcome multi-layered air defense systems, including the US Patriot and THAAD systems.

The state news agency IRNA described the Qasem Basir missile as a tool to implement a new doctrine aimed at countering threats before they materialize. The introduction of this ballistic missile signifies a pivotal moment in Iran's defense strategy, marking a shift from reactive deterrence to proactive deterrence.

In a social media post on September 8, Rezaee reiterated that the US had received clear warnings from Iran's new missile capabilities, stating that economic warfare would be met with a maritime exclusion zone extending throughout the Persian Gulf.