Drones, once auxiliary to the war on the ground, have grown into a giant-slaying weapon in Ukraine’s arsenal over four years of ingenuity, writes James C. Reynolds The explosion was so powerful that it sent the huge disc-shaped lid of an oil storage tank flying high above the city on a cushion of black smoke and flame. Ukrainian drones cut through the Russian air defences last week to strike an oil refinery in ... [5910 chars]