President Lee Myung-bak will embark on a three-day visit to China on Monday. His visit, coming several months ahead of the 20th anniversary of Seoul-Beijing diplomatic relations, will surely provide an opportunity for Lee and his Chinese counterpart, Hu Jintao, to review past achievements and map out the future course of action.

South Korea and China, the only military ally of North Korea, have come a long way since they established diplomatic ties in August 1992. A retired Chinese diplomat, who was deeply involved in the negotiations on the opening of formal ties with Seoul, is quoted as saying that Pyongyang had consistently voiced opposition to Seoul-Beijing official ties.

One notable event in this regard was Lee’s 2008 agreement with Hu on upgrading the ties to a “strategic cooperative partnership.” Under the partnership, Hu said, China and South Korea should expand bilateral trade, promote security cooperation in Northeast Asia and help each other in other areas.

Indeed, bilateral trade grew so rapidly that it did not take long before China replaced the United States as the largest trading partner for South Korea. Moreover, bilateral trade still has huge potential for further growth.

But the strategic cooperative partnership has hardly lived up to its namesake in areas other than trade. A case in point is Lee’s failure to put a telephone call through to Hu when Pyongyang announced Kim Jong-il’s death on Dec. 19. Were China South Korea’s strategic cooperative partner to the fullest extent possible, Lee would have had little difficulty discussing the security implications of Kim’s death with Hu on the phone. Regrettably, no such conversation materialized.

Strategic partnership can roughly be defined as “a long-term commitment by two important actors to establish a close relationship across a significant number of policy areas,” as suggested by one scholarly paper. Nonetheless, the term remains vague enough to mean one thing to one party and another to the other. Add “cooperative” as another qualifier, and it becomes even more complicated.

Semantics aside, a strategic cooperative partnership can be reduced to a hollow diplomatic slogan when it is to be understood in connection with Pyongyang in China’s case and with Washington in the case of South Korea, with the United States being its sole military ally. That is the unmistakable limit to the partnership.

As such, South Korea has no reason to complain about China’s tilt toward Pyongyang. In other words, Lee should refrain from reading too much into the agreement on a strategic cooperative partnership when it comes to South Korea’s security concerns about the post-Kim Jong-il North Korea. China will stay the course when it finds it fit to serve its own security interests. So will South Korea.

Instead, Lee will do well to focus on areas from which the two countries can derive mutual benefits. One such area is bilateral trade. They can further promote it by making the best use of their geographical proximity and complimentary industrial structures. But caution is advised to Lee when it comes to China’s proposal to hasten negotiations on a bilateral free trade agreement and a trilateral one, which would involve Japan as well.

True, a free trade agreement would give South Korea security benefits as well, because it would undoubtedly bring Beijing closer to Seoul. Before making any commitment, however, Lee will have to consider the implications that an upsurge in agricultural imports from China, which would follow a free trade agreement, would have on domestic politics. He will also have to weigh it against an anticipated increase in the exports of industrial products to China.

Moreover, trade experts advise that South Korea take some time to make the most of the existing trade deals, in particular those with the United States and the European Union, instead of plunging into negotiations on new ones. In other words, they say Seoul needs some breathing space.

One area that demands the two leaders’ immediate engagement is the worsening conflicts between the South Korean Coast Guard and China’s poaching fishing boats, as seen in the recent slaying of a South Korean officer by a Chinese captain. Lee has to call on China to keep its fishing vessels off South Korea’s exclusive economic zone.