The US base on the island of Diego Garcia, in the middle of the Indian Ocean, is among the most important US military facilities in the world, and is the foundation stone of the US presence in the Indian Ocean region. It’s been a vital element in Australia’s strategic position in the region for almost 50 years. But the dispute over ownership of the island is now creating serious uncertainties over the continued long-term US military presence. Australia’s position on the controversy is becoming increasingly untenable and now needs to be reviewed.