In recent months, for instance, the widely followed Shanghai Composite Index has risen whenever investors have thought that Chinese officials would intervene to pump up the economy and has fallen whenever they, contrary to expectations, have not done so.

FORBES: China Bull Loses Fortune, Stays Bullish

The transaction will only turn out to be important if it is the priming of a financial pump that then gushes a flow of Chinese money into British roads, rail, hospitals and the other things that our indebted government is struggling to afford.

BBC: Why the chancellor wants China's cash

Mr. YERGIN: Ten years ago the thought that would happen in a Chinese oil market could possibly have had an impact on what motorists in America pay at the gasoline pump would have seemed just unrealistic.

NPR: Oil Prices Likely to Stay High Next Year