Iran appears to have launched a Qasem Basir missile, described as a "turning point in defense strategy", and forced the US aircraft carrier to dodge.
"48 hours ago, we tested a special anti-ship missile right above a US warship for the first time. This weapon caused a nightmare and forced them to flee," Mohsen Rezaee, Advisor to Iran's Supreme Leader, said on September 6.
The statement was made a day after Iran's Islamic Revolutionary Guard Corps (IRGC) accused US warships of participating in a maritime blockade campaign and "harassed" ships, affirming that they had conducted a raid and forced two enemy naval vessels to "leave the combat area".
Central Command (CENTCOM), the agency in charge of operations of US forces in the Middle East, on September 5 confirmed that the IRGC launched many ballistic missiles against two naval ships patrolling the area. "An aircraft carrier and a destroyer successfully avoided a series of attacks from Iran. No US military personnel were injured in the incident," the agency said.
Brandon Weichert, a geopolitical analyst in the US, noted that CENTCOM's announcement showed that Iranian ballistic missiles were indeed threatening the warship fleet.
"The aircraft carrier will not suspend flight operations and begin evasive maneuvers unless the missile penetrates the defense layers and approaches so close that it becomes a serious threat. The US Navy is having to deal with this threat with a force of destroyers that are increasingly stretched and worn out by war," he said.
He also recalled the incident where an American F/A-18 multirole fighter crashed into the Red Sea when the aircraft carrier USS Harry S. Truman had to make a sharp turn to avoid Houthi ballistic missiles last year.
Iranian officials did not specify the missile model used in the incident, but the country's media said it was the Qasem Basir series. Military website Defense Security Asia commented that this may be the first time this type of missile has been deployed in real combat.
Qasem Basir is a two-stage medium-range ballistic missile that uses solid fuel, has a range of about 1,200 km and was launched in May 2025. This is an upgraded version of the Haj Qasem medium-range ballistic missile that Iran announced in 2020.
According to the Institute for the Study of War (ISW), headquartered in the US, the Qasem Basir missile is designed to apply the lessons learned by Iran after retaliatory raids in 2024, in which US and Israeli ballistic missile defense systems shot down the majority of enemy weapons.
Qasem Basir has an estimated length of 11 m, launch mass of 7 tons and carries a warhead weighing 500 kg. The projectile is said to reach a speed of 13,600 km/h, 11 times the speed of sound, during reentry and 6,200 km/h at the time of impact with the target.
Within the framework of the Defense Achievement Exhibition in 2023, Iran also introduced new capabilities of the Haj Qasem series, which significantly shortens the time to change status and be ready to launch bullets compared to previous systems.
This improvement stems from modifications to the launcher structure. Western experts believe that the missile uses a dynamic reference unit (DRU), which provides high-precision real-time navigation data by integrating accelerometers, gyroscopes and even magnetometers.
Thanks to the support of the DRU, the launcher can immediately reach the optimal firing angle right after changing the status from marching to ready to fire. This technology has been applied to the Kheibar Shekan and Fateh missile complexes, helping to reduce preparation time to 1/6 compared to other models, according to Iranian officials.
The Qasem Basir missile has eight stabilizing wings on the tail and does not use a thrust vector control system like some other Iranian missiles, but still seems to achieve the necessary maneuverability thanks to the rudder cluster and the ability to adjust the trajectory in the final phase.
Iranian officials confirmed that the Qasem Basir has been significantly revised in its warhead design, helping the missile maneuver more effectively and evade enemy air defense systems.
Compared to the original Haj Qasem model, the Qasem Basir missile has a significantly upgraded guidance system.
Haj Qasem uses an inertial navigation system (INS) combined with GPS satellite navigation, in which the projectile follows GPS data at the beginning and middle of the journey, before using INS in the final phase.
The reason Iran chose this option is that GPS can be jammed by electronic warfare systems, while INS uses accelerometers and gyroscopes to correct flight paths, not affected by suppression measures. However, the accuracy of this method is significantly lower than GPS correction in the final phase.
Experience from fighting with Israel, especially the requirement for high accuracy and resistance to interference, led Iran to integrate optical-electronic or infrared sensors for Qasem Basir missiles. This system not only increases missile accuracy, but is also immune to electronic warfare.
Optical-electronic and infrared guidance mechanisms in the final phase have been used by Iran on a number of previous short-range ballistic missile models, but they mainly only target targets 300-500 km away, significantly shorter than the Qasem Basir.
The disadvantage of the above navigation method is that the flight range is reduced. This gives Qasem Basir a maximum range of 1,200 km, compared to 1,400-1,800 km for Haj Qasem.
Press TV stated that Qasem Basir is capable of hitting even targets that require the highest precision, such as the entrance to an aircraft hangar or a warship moving at sea. "Video of the test launch shows Qasem Basir hitting the target's bull's eye, proving that this rocket model has accuracy in decimeters instead of meters," Iran's news agency said.
In 2023, then-Iranian defense minister General Aziz Nasirzadeh announced that the Qasem Basir missile had accurately attacked targets at a distance of more than 1,200 km without depending on GPS, under conditions of strong electronic suppression.
He emphasized that weapons have been enhanced in both guidance systems and mobility, capable of overcoming multi-layered air defense systems, including the US Patriot, THAAD and Israeli Arrow complexes.
Iran's state news agency IRNA on September 7 called the Qasem Basir missile a tool to implement the new doctrine, which is "action to counter all threats before they become reality".
"The launch of the Qasem Basir ballistic missile marks a turning point in Iran's defense strategy. This is a missile that not only has greater range and accuracy, but also symbolizes a change from the reactive deterrence model to proactive deterrence," IRNA said.
In an article posted on social networks on September 8, Mr. Rezaee once again mentioned Iran's "new missile". "In recent days, the US has received a clear warning from Iran's new missiles. The economic war will be responded to by a maritime ban stretching across the Persian Gulf to the blockade belt," he said.
