In the public perception, it is almost axiomatic that overseas oil assets constitute energy security. It assumes that ownership confers rights of unqualified access. There is a belief that if you own hydrocarbon assets in any corner of the world, it automatically and ineluctably entitles you to physically access those resources as and when you need them; in fact, especially when you need them in the event of a sudden disruption in global oil supply arising from natural disasters, terror strikes or political disturbances.