London, Oct. 30 -- Gulf states may need to overhaul their trillion-dollar defence strategies after Iranian attacks exposed shortcomings in their military capabilities and raised questions about the continued value of US bases in the region, according to a study by the International Institute for Strategic Studies (IISS).

The report said 12 countries, mostly in the Gulf, faced 4,670 Iranian one-way attack drones and more than 1,400 ballistic missiles in the weeks before the 8th April ceasefire. Nearly half of the attacks were directed at the UAE. Although most were intercepted, the damage to energy infrastructure has been estimated at as much as $58bn (£43bn).

Despite heavy investment in predominantly US-made weapons, the study identi...