China, the behemoth? Not so fast.

In a way, the United States is getting a taste of its own medicine. When a Chinese state oil firm, CNOOC, made a bid this month for an American oil producer, Unocal, it made front-page news.

And rightly so. It spotlighted the growing economic might of populous China and its drive to ensure an adequate supply of energy for its exploding economy. China has recently replaced Japan as the biggest importer of oil in the world after the US. The bid also raised concerns that China, like Japan in the 1970s and 1980s, will use its growing stock of US dollars to buy up more American firms.

But China's foreign direct investments are so far chicken feed compared to those of the US.

In the past four years, China has sunk at least $11 billion into foreign plants, offices, and firms. Perhaps some Hong Kong money should be added to that total. Hong Kong, now part of China, made $39.7 billion of foreign direct investment last year, and $24.3 billion over the previous three years combined. Some of that investment may be money from China's mainland escaping government attention.

The US, though, has invested almost $700 billion abroad in those four years.

"That's a completely different magnitude," says Hans Christiansen, an expert at the Organization for Economic Cooperation and Development (OECD), the club of mostly industrial nations based in Paris.

Last year alone, outflows of foreign direct investment from the US reached an all-time record of $252 billion, up from $141 billion the year before.

The $19 billion bid by China National Offshore Oil Corp. for Unocal is not only China's biggest overseas move yet. It also has what Mr. Christiansen calls "an element of strategic investment." China has been making smaller investments around the world in minerals, coal and other hydrocarbons, agriculture, and fisheries.

Nonetheless, to Albert Keidel, China's Unocal bid is "a minor blip that gets more PR noise than it deserves." As the senior associate at the Carnegie Endowment for International Peace sees it, as long as China plays by global investment rules, it should be eligible to compete with Chevron for Unocal.

"The highest bidder should get the deal," he says. "We need to get used to this sort of thing." He suspects some opposition to the Unocal bid has a "racial dimension." The bidders are not Caucasian.

There's some speculation that Washington could block the deal. It may be reluctant to let China, with its authoritarian regime and new interest in purchasing more arms, pick up Unocal with oil and gas reserves not only in the Far East but in the US itself.

China itself is not keen on selling its own business properties.

Even before the Unocal bid, Congress was worried about the flood of Chinese imports and the failure of China to revalue its currency. Last year, the US deficit with China was $162 billion, or 24 percent of its total trade deficit.

To many economists, China's trade surplus with the US does not necessarily mean that the yuan is overvalued.

"The more meaningful statistic is a country's global trade balance" with all nations, notes Mr. Keidel. That is "not excessively or unfairly large."

Indeed, in relation to China's gross domestic product, that is, its total output of goods and services, China's global surplus is smaller than that of Germany, the Netherlands, Thailand, Argentina, Malaysia, and Singapore.

Moreover, much of the pileup of dollars in China's central bank has not been due to a trade surplus, but rather to both genuine long-term foreign investment and speculative inflows.

By the end of 2004, China's foreign-exchange reserves had risen from $200 billion to $600 billion in just three years. In a new report, the OECD counts $151 billion of foreign direct investment in China in the past three years. Keidel calculates that $150 billion to $250 billion of the buildup in dollar reserves in China's central bank is due to speculative inflows, despite China's capital controls. Foreign investors have been putting huge amounts of money into Chinese real estate, possibly creating a property price bubble. The investors hope to get a special profit kick from a revaluation of the yuan at some point.

That hasn't happened yet. In the future, some hot money could leave China in a rush. This could prompt China to use its dollar reserves to defend the value of the yuan.

Another economist, Nouriel Roubini, of New York University, suspects one factor in the Unocal bid could be a desire of China to diversify its dollar reserves out of low-paying US Treasury bills into investments with a better prospect for a higher return.

CNOOC is 70 percent owned by the Chinese government. So it is unlikely it would make the Unocal move without the assent of Beijing officials.

Mr. Roubini is concerned that the massive current account deficits of the US - "on the way to $800 billion" - will soon blow up the international monetary system that has evolved since the end of World War II. Already, foreign central banks, including that in China, hold more than $1.2 trillion in US Treasury debt. "At some time, the rest of the world is going to become tired of financing the US deficit," he says. That would clobber the dollar and hurt the world economy.