Welcome to the inquiry on the BBC World Service with me Ruth Alexander. Each week we bring you four expert witnesses answering one pressing question from the news.

Let me take you to fiery cross reef, a ridge of jagged rock and coral just above the surface of the South China Sea between Vietnam and Indonesia, a complex ecosystem home to hundreds of

species of fish and other marine life, until three years ago when the dredges arrived and ships full of concrete and rubble.

First a harbour appeared, then a runway, and aircraft hungers.

In a matter of months, the rocky outcrop had been transformed from a pristine reef in the middle

of the ocean to a fully equipped Chinese military base.

Firery Cross Reef is one of several new militarized man-made concrete islands, created by the Chinese in waters that are contested by six nations.

The South China Sea is a small sea. You may never have given it much thought, but as new pitches have emerged

in the last few weeks of China's audacious building project there, some fear it's at risk of becoming a flashpoint that could trigger a conflict with

global consequences. So in this inquiry we want to know what does China want in the South China Sea. Part 1, Nation Building.

Nation Building.

First, let's set the scene. The South China Sea is a little smaller than the Mediterranean.

It lies between the Indian and Pacific oceans and is surrounded by seven countries, China, Taiwan, Vietnam, Malaysia, Indonesia,

Brunei and the Philippines.

All except Indonesia make claims to the sea and the tiny uninhabited islands dotted around it.

So let's meet our first expert witness.

I think I am in a privileged position.

Fengchong is a specialist in Chinese international relations at the Australian National

University.

I'm still a Chinese citizen, but a permanent resident in Australia.

I travel to South Southeast Asia quite often as well.

So I hope to develop a balanced view regarding this very controversial and strategically consequential question.

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