In reality, however, conflict deterrence and peace promotion in the Asia-Pacific region stem from the military presence of the United States, especially from the forward-deployed US Navy. Only the US Navy possesses the strength and capability to guarantee sea control throughout the entire Asia-Pacific region. Furthermore, only the US enjoys the trust of most of the regional states due to its obvious lack of territorial ambitions. A variety of sources of instability threaten the Asia-Pacific region; but, as long as the US remains engaged, it is possible effectively to prevent conflict from erupting. Fortunately, the US presence remains in keeping with its own national interest of maintaining peace and stability in the region, preserving a balance of power to prevent the emergence of a regional hegemon, and guaranteeing freedom of navigation.
Various types of bilateral and multilateral exercises between the US and the navies of its allies and friends take place annually in the seas off Hawaii, Japan, Korea, Australia, Thailand, and the Philippines. These exercises demonstrate US commitment to the region and the ability to organise coalitions, and to improve interoperability. Some impediments in forming effective cooperation remain in the region however. Differences in security policies among regional states are the most notable obstacles to the formation and development of coalitions.
These impediments include legal constraints within regional states, the inability to share applicable technology or technical publications, and unresolved command structure issues. Three examples of such impediments which hinder regional cooperation include: legal constitutional hurdles prevented Japan from taking part in the Gulf War and continue to prohibit Japan's coalition participation except for limited bilateral cooperation with the United States; the absence of mutually held operational publications or advanced technology has hindered combined training and effective operations and has frustrated cooperating counterparts for many tears; and the regional states are reluctant to accept foreign command of their forces.
However, in Northeast Asia, remarkable progress has been observed in a Korean-Japan track two security dialogue on maritime cooperation. Dialogue participants have reached a conclusion that Korea-Japan naval cooperation is best suited and is the most attainable course of action.5
In the US-Japan joint security declaration in April 1996, the leaders of the two nations publicly expressed their strong convictions to revitalise the US-Japan alliance in the wake of the Cold War. They confirmed the purpose of the alliance is not only to defend Japan, but is also to cooperate in the maintenance of stability in the Asia-Pacific region. As such, the declaration represented an epoch-making step in achieving regional peace and stability.
Meanwhile, we can detect some movement within the US-Korea alliance towards preparing for a similar role in ensuring regional stability once Korean reunification has been achieved. If this latter effort is realised, both the US-Japan and US-Korea security arrangements will serve to support the forward deployment of US forces. Japan and Korea will supplement US forces, and a functionally overlapping security system covering a broad scope of activities will result.
If both Japan and Korea wish to maintain US military presence efficiently, some sort of common framework must be established among the three nations. However, they must deal with some obstacles to realise a healthy and functional trilateral system of cooperation. Some impeding factors include long-standing distrust, no precedent for security cooperation, Japan's self-imposed restriction on exercise of collective defence right, and China's sensitivity, if not hostility towards potential Korea-Japan-US security cooperation.
Fortunately, positive dynamics that may propel trilateral security cooperation forward include overlapping SLOCs on which both Japan and Korea absolutely depend for national survival and prosperity, shared political and economic values, and existing security treaties between the United States and both Japan and Korea.
