The U.S. government's lighter than expected tariffs on China's solar panel imports reflects some degree of rationality, but it has to do more to keep bilateral trade ties from derailing.

The U.S. Department of Commerce announced Tuesday that a preliminary investigation found that Chinese solar panel makers have received government subsidies of 2.9 percent to 4.73 percent, and decided to levy the same amount of tariffs on Chinese imports.

Although the evidence leading to the ruling does not seem convincing, the subsidy margin is smaller than the estimated scale of up to 10 percent, which is, to some extent, a result of compromise.

Before the decision was made, the solar panel case was a topic of heated debate in the United States. It is well-recognized domestically that the stiff tariffs' devastating impacts on the affordability of solar power use and the U.S. solar power industry will outweigh its positive impact on job creation.

The vocal domestic calls and a cautious measure between pros and cons have given rise to Tuesday's ruling. The Commerce Department will announce in mid-May whether Chinese companies are dumping solar panels below costs, and a similar psyche is hoped to be implemented by the U.S. government in making the decision.

Although the solar panel case has proven to be less devastating than expected, the U.S. government recently intensified shots against a range of Chinese imports, from rare earths to steel wheels, recalling the phantom of protectionism in an election year.

China, among other emerging economies, is a beneficiary of free trade principles. It is committed to following the principles of the World Trade Organization, but will not bend to the standards of a handful of countries.

The U.S. should gradually learn to adapt to a marketplace in which emerging countries are playing more active roles by sharpening its own capabilities in innovation and lowering costs, and not resorting to protectionist moves to shun obligations.

When conducting subsidy and dumping probes, the U.S. government should make decisions based on facts. Punitive duties, big or small, will distort normal trade relations and risk disturbing the fragile global economic recovery process.

Good trade will serve as a ballast stone, not a stumbling block, for the economic vessel to navigate choppy waters. In a time of crisis, the U.S. government should keep that in mind.