For what it’s worth, I strongly disagree that Korea-Japan ties “are at their lowest ebb since the two countries normalised relations in 1965″—I remember late President Roh Moo-hyun’s “diplomatic war” all too well—but this piece in The Economist was still interesting.

Of particular note is that the “hub and spokes” structure of America’s East Asian alliances does not promote regional security cooperation ala NATO. This is to say South Korea cares about America, and Japan cares about America, but Seoul and Tokyo care little about one another:

America’s problem is that for Japan and South Korea, the direct costs of falling out are bearable. South Korea’s tourist industry has taken a hit, but trade and investment flows continue. Nobody expects Japan to go to war over Dokdo/Takeshima. And some trilateral co-operation with America persists—over North Korea, for example. This week the three countries met in Washington to discuss curbing the North’s nuclear aspirations. Poor Japanese-South Korean relations can scarcely be blamed for the lack of progress on the North’s proliferation.

For Japan’s military ambitions, South Korean opposition matters far less than America’s encouragement; and for South Korea the lack of “spoke-to-spoke” security relations with Japan matters less than ties with the hub, America. So, rather than making its allies susceptible to pressure to co-operate, America’s security guarantees in effect facilitate their quarrelling. A strong trilateral alliance might alarm China and cause it to rethink the backing it provides North Korea—but South Koreans worry it might also make China more hostile to Korean unification.

A comforting poll in September by the Asan Institute, a think-tank in Seoul, showed 58% of South Koreans in favour of a Park-Abe summit without preconditions. But in neither country do leaders face strong popular demands to make up with the other. Unless the dangers of their quarrels become more evident, a slide into even sharper acrimony seems unavoidable.

I’d love to see greater security cooperation between Seoul and Tokyo, and we almost had it at one point during the Lee Myung-bak administration before everything suddenly went to shit. The problem, at least in South Korea, is that while Seoul is very happy to work with the United States (and, for that matter, Japan) when in comes to North Korea, it’s much less willing to do so when it comes to China, Korea’a largest trading partner and, allegedly, a major influence in Pyongyang.

I imagine this is going to be doubly so during the administration of President Park, who strikes me as something of a Sinophile.

Japan, meanwhile, is more than happy to stick up to China and probably would like Seoul’s help in doing so, but backed by a bilateral alliance with the United States, it has little reason to display the Willy Brandt-esque statesmanship to make greater security cooperation with Seoul politically feasible.