From the air, the Spratly Islands, a cluster of miniature rocks and sandbars 425,000 kilometres square in the middle of the South China Sea, are almost imperceptible. Even up close, the Spratlys do not look like much – a few islands have tiny rocky beaches or occasional makeshift buildings. A tiny contingent of Filipino marines camps on a rusty hulk of an American ship from the Second World War grounded in the Spratlys.

It’s hard to believe these outcroppings could be at the centre of an international dispute, let alone one that could lead to a future Asian war. But the Spratlys are not only claimed by China as Beijing’s exclusive economic zone. The Philippines, Vietnam, Malaysia, Indonesia and Brunei angrily retort that parts of the South China Sea belong to them, including areas that Beijing insists is China’s alone.