evidence: When you stand on the island of Rukwanzi at the heart of Lake Albert, your first thought, echoing perhaps the casual rhetoric of the region’s oil men, is that you are at the edge of a new frontier. But for its communities the lake is a centre, a point of connection and integration, the great body of water into which the White Nile flows, part of the vast rift valley that draws Africa’s citizens into mutual dependency. What happens here matters to half a dozen neighbouring countries. But the lines being drawn now, as neat and straight as the borders on colonial maps, mark not sovereign territory, but exploration blocks for oil and gas companies. Just a few miles from Rukwanzi six Congolese were killed in September 2007, shot at by the Ugandan army while they travelled in a passenger ferry from the island to the DRC shore. It was revealed last week that Heritage Oil and Gas, the British wildcat explorer founded by former mercenary Tony Buckingham, played a key role in triggering that military operation after its staff had crossed illegally into Congolese waters.