BEIJING, Feb. 27  -- As China rises to be a crucial player in the world economy, the United States is demonstrably attempting to exploit its growing business links with the Asia giant as a political bargain chip.

Chinese investors faced the heaviest scrutiny in the United States for the second straight year in 2013, with many of its high-profile investments hitting snags for "national security" reasons in the market claimed to be the world's most open and freest, a recent report has revealed.

For years, the notorious examinations conducted by a Treasury-led panel, or the Committee on Foreign Investment in the United States (CFIUS) on the national security implications of foreign investment, have been the major concern for Chinese companies eyeing the U.S. market.

The continuation of discriminatory reviews against the Chinese investment might also frustrate the seven-year-long negotiation between Beijing and Washington over a bilateral investment treaty, which will eventually be detrimental to both sides.

It is understandable that the influx of Chinese investment into the world's biggest economy in recent years could incur speculations and even uneasiness from some recipient countries.

And indeed, a sovereign government may be justified in saying no to foreign investment out of national security concerns, yet such a mechanism should never be exploited or abused as protectionism in disguise, or used as a political weapon against another country.

In a move that seems to the follow U.S. lead, its Asian ally the Philippines has announced suspending a Chinese company's involvement in the construction of the country's power grid, also citing "national security concerns".

This is not only a flagrant violation of business ethics, but also lays bare Manila' s short-sightedness and asininity.

The United States, the world's sole superpower and the largest economy, has long portrayed itself as a victim of plots and conspiracies from the outside world.

Yet, as a matter of fact, Uncle Sam itself is the one that poses the gravest and the most ubiquitous threats to other countries, as manifested by the Edward Snowden scandal, among others.

As a key trader and investor in the global economy, China is actively sharing its development opportunities with the rest of the world and contributing to the development of many other countries. The Chinese enterprises operating overseas have been duly advised by the government to abide by rules and regulations in their host countries.

Behind the predicament Chinese investors are facing in America are the ups and downs of the China-U.S. relationship. In an increasingly interdependent world, the two largest economies, despite political and ideological differences, should become friends rather than enemies, partners rather than rivals.