 ATACMS missiles changed the course of the war in Ukraine, putting Russia in a difficult position. Experts at the Institute for the Study of War ISW have analysed the implications for Russia of Ukraine's deployment of long-range ATACMS missiles, which would pose a threat to Russian aircraft and their ammunition storage points in the rear. The report stated that Ukraine had used the US-provided ATACMS long-range missiles for the first time to strike Russian targets in the country's occupied territories on the 17th of October. The Wall Street Journal and other Western media outlets confirmed that the US had secretly provided Ukraine with 165-kilometre range ATACMS missiles over recent days and reported that Ukrainian forces had actually made use of ATACMS missiles to strike airfields in the Russian-occupied cities of Burdiansk, in Zaporizia Oblast, and Luhansk. Ukrainian President Volodymyr Zelensky also said that ATACMS had proven themselves well but did not explicitly confirm their use during these strikes. Analysts point out that the US likely transferred the ATACMS systems secretly to provide the Ukrainian forces with an operational surprise and the general shock in the Russian information space indicates that Ukraine has achieved the desired effect. They also add that the likely scattering of Russian aircraft at airfields across occupied Ukraine and the movement of aircraft further away from the contact line is likely to disrupt Russian air support for defensive efforts and local offensive operations. Relocating aircraft to airfields further to the rear may affect the loiter time that Russian aircraft will have to support operations. Experts suggest that this will be particularly challenging for Russian helicopters which have been operating in relatively small areas of the frontline for a long time to weaken the advancing Ukrainian mechanized forces at the start of the counter-offensive in June and July 2023. The dispersal of air assets to more airfields will also likely present the Russian aerospace forces with greater challenges in coordinating and sustaining operations. The emergence of long-range missiles also poses a significant threat to Russian ammunition storage points in the rear areas and is likely to force the Russian command to choose between fortifying existing points and further dispersing them throughout occupied Ukraine.