sdl: china's strategic prize (1 and only left), page-9

What i dont understand is if RIO/BHP etc know how big SDL is,and know the chinese are after it,why dont they intercept it and take it off them? that way they still hold the monopoly and control on ore prices and supply and the chinese will still have to buy off them,keeping prices up.
Its a bit of a puzzle to me.
Wouldnt RIO/BHP be worried if they get there hands on it they will not have to rely on them anymore?

Opinion guys


cheers Indigo