For some time now Washington has tried to talk Tokyo into upholding its end of mutual security burdens in light of Japan's markedly improved economic situation. It is time to look to another Northeast Asian ally - the Republic of Korea - for the sorts of assistance Japan is unwilling to provide. South Korea, too, has an immense direct stake in protecting the Western Pacific and Indian Ocean SLOCs (Sea Lanes of Communications) and in maintaining peaceful conditions in the Middle East which assure Seoul of reliable supplies of vital oil for its dynamic economy.
As one of Asia's ''new Japans,'' South Korea proportionately has as great a stake in these matters as Japan does. Moreover, Seoul has expended much effort and enjoys considerable success in cultivating economic contacts in Southeast Asia and the Middle East, appealing to both regions as an alternative to Japan.
Most important, Seoul would be far more likely to be forthcoming if Washington were to request South Korean armed assistance covering the SLOCs and participating in Mideast peacekeeping.
Given its problems with North Korea, the ROK obviously could not offer large-scale assistance. At most it might be capable of devoting token numbers of small ships or planes to SLOC protection duties.
More significantly, South Korea might be able to dispatch a battalion or two of ROK ground forces to supplement US Rapid Deployment Forces. In this regard, South Koreans already have speculated about the advisability of sending ROK forces for Lebanon peacekeeping and decided not to. It clearly would take Seoul some time to gear up for any role of this sort, but the South Koreans probably could do it. Any such ROK assistance in bolstering the US strategic presence in the Pacific and Indian Oceans would be intrinsically valuable and would cement further already close US-ROK ties.
There is a more important reason the US should seek help from the ROK. If the ROK steps in to lend a hand at tasks Japan has refused, it will put South Korea clearly in the position of upholding part of Japan's responsibility. Seoul long has pointed to the disparity in the percentages of GNP each of America's Northeast Asian allies spend on national defense as evidence that South Korea provides a security buffer shielding Japan. That argument was rejected by Japan despite Prime Minister Nakasone's recent agreement to provide large-scale economic aid to Korea - assistance Seoul initially requested on grounds of strategic reciprocity.
Tokyo's denial of such security benefits may be plausible vis-a-vis the Korean peninsula for reasons of Japanese political sensibilities. However, if Seoul starts doing some of Japan's duty in the SLOCs and Middle East, it will be difficult for Tokyo to obfuscate the benefits. Such a Korean role would be useful for Seoul intrinsically, as an expression of its support for US-ROK shared interests and as extra leverage in its dealings with Tokyo.
From Washington's perspective, South Korea's possible assistance should be valued for its own sake and for its potential impact on Japan. Tokyo might simply accept it as an additional ''freebie.'' If this happens, the US would not be any worse off than it is today. Washington still would have gained one small helping hand where today it has none. However, it is unlikely that Japan could tolerate passively the humiliation of another Asian country doing Japan's duty - particularly if it is South Korea. Having Americans do Japan's job may seem wise and crafty to Tokyo, but being shown up by Koreans would be galling to the Japanese sense of pride and honor.
The peer pressure resulting from such a loss of face, probably exacerbated by Koreans' willingness to play their role to the hilt, could well stir Japan to meet its responsibilities to help the US bear the burden for regional security. Since this is precisely what Washington pursues today, and given Japan's potential for far more than a token role, why not try to utilize indirect South Korean peer pressure to accomplish worthwhile American goals?