The United States and its East Asia allies on Saturday agreed to further study possible trilateral information exchanges about the North Korean missile threat.
The heads of defense for Washington, Seoul and Tokyo during a three-way discussion in Singapore "reaffirmed the importance of information sharing on North Korea nuclear and missile threats and shared an understanding that this issue needs to be reviewed further," says a joint statement released after the meeting.
No mention was made in the statement from U.S. Defense Secretary Chuck Hagel, Japanese Defense Minister Itsunori Onodera and South Korean Defense Minister Kim Kwan-jin about an official agreement being reached that would enable the direct sharing between Japan and South Korea of sensor data related to North Korean missile launches. Such a pact was earlier envisioned to result from the sit-down, which happened on the margins of the annual Shangri-La Dialogue in Singapore.
Patrick Cronin, senior director of the Asia-Pacific Security Program at the Center for a New American Security, said that despite the lack of a big commitment in the joint statement, Saturday's discussion actually did produce a significant breakthrough in U.S. efforts to boost regional missile defense cooperation.
The newly reached understanding described in the joint statement only covers information sharing related to the North, something that appeases Seoul, he said in a Monday phone interview. An earlier Japan-South Korea draft deal on intelligence sharing foundered two years ago in part over Tokyo's desire to exchange information about both North Korean and Chinese missile threats, according to Cronin.
And Japan achieved its goal of getting the issue of intelligence cooperation with the South back on the regional agenda, Cronin said.
"So they each got something," he added, noting that any formal information-sharing agreement would still be subjected to legislative approval in the East Asian countries.
Currently, there are bilateral information-exchange agreements in place between the United States and Japan, and between the United States and South Korea.
This has created a "bit of a hub-and-spoke model, with the U.S. in the middle talking to the Japanese on one side, talking to the Koreans on the other," said an unidentified senior Defense Department official accompanying Hagel on his trip to Singapore in a briefing with journalists.
South Korea is building a domestic antimissile framework -- the Korea Air and Missile Defense system -- that will involve updated Patriot Advanced Capability 2 and PAC-3 interceptors aimed at defending against a lower-tiered missile strike launched by the North.
"That makes sense, you know, for where they sit right now," the unnamed Pentagon official said. "But the key is to get it interoperable and integrated into one system that is [as] effective as possible."
In the case of East Asia antimissile cooperation, "interoperable" refers to the ability of different systems to pass domain awareness data to one another, including possible real-time information, Cronin said. System "integration" goes beyond that, by enabling separate technologies to work together to formulate an "instantaneous" intercept plan in response to a detected missile firing.
While the South appears to be "willing to go along" with the goal of achieving system interoperability with Japan and the United States, for now "they are not willing to have a permanently fixed, integrated early-warning and shoot-to-kill missile system" with the two countries, Cronin said.
U.S. antimissile cooperation with Japan, meanwhile, is already further along.
The United States is scheduled by the end of the year to deploy the second of two early-warning radars on Japanese territory and is slated by 2017 to redeploy two more Aegis-equipped warships to the island country.
While Seoul has decided against purchasing Aegis missile interceptors that could be used against higher-altitude threats, Tokyo has its own Aegis fleet. Additionally, Japanese firms are collaborating with U.S. defense companies to produce a next-generation Standard Missile 3 interceptor deployable both on Aegis vessels at sea and on land.