An unprecedented attack using unmanned aerial vehicles or drones on Saudi Arabian petroleum giant Aramco’s oil-processing facilities, reportedly by Yemenese Houthi rebels, has shaken up the Indian and world markets. Following Aramco’s confirmation that it would shut down half its output — almost 6 million barrels a day, 5 per cent of global production — oil prices showed an intra-day increase of almost 20 per cent, the largest such spike in recent years. Effectively, all the spare processing capacity in the system has been wiped out. Much now depends on how soon Saudi Arabia can bring some of it back