China, the United States, Japan and Russia are four major powers which have great influence on international affairs in the Asia-Pacific region and the world as a whole. However, the role of each of the four nations is quite different due to two main factors:

Firstly, in terms of “comprehensive national strength”, the United States is the sole superpower in the world today, which has the greatest political, economic, military and cultural influence in the world. Japan is the second largest economic power, but its political influence is limited because of historical and political reasons. Russia is, of course, no longer as strong as the former Soviet Union and presently in a period of political instability and extreme economic difficulty, but it still remains a major power of great importance with its military strength just next to the United States. China is an emerging developing nation. Although its “comprehensive national strength”, particularly its economic, science and technological and military strength, falls far behind that of the United States, it has a large political influence among developing countries. Secondly, in international organizations, China, the United States and Russia are the permanent members of the UN Security Council. Japan is striving to be a permanent member of the Security Council, but it seems to wait a rather long period of time. Nevertheless, Japan, together with the United States and Russia, has joined the G-8, while China is not a member of the group.

As the G-8 increases its role in world political and economic affairs, China’s influence on international affairs could be affected to some extent. Moreover, the United States enjoys the greatest influence in the World Bank and the International Monetary Fund (IMF). Japan also has influence in the two organizations. China and Russia have little say and both are debtor nations. Furthermore, the United States and Japan are members of the World Trade Organization, while China and Russia continue to be excluded from that organization. All this reveals a complex relationship between the four major powers where there coexists both common interests and contradictions, cooperation and competition, interdependence and mutual restraints between them.

Such a complex relationship is reflected in many areas of world affairs. Due to limited space, this paper will focus the discussion on the following four areas: the United Nations, peace and security, disarmament and arms control, and the international economic order, and put forward some suggestions for removing the contradictions and strengthening their cooperation in international affairs.