Rapid growth is transforming the economic landscape of East Asia. Together with changes set in motion by the end of the Cold War, it will transform the strategic landscape as well, creating a need for new structures to maintain stability and defuse tensions.

The security problems today in East Asia pale compared with those faced by the region in the past. The area is more or less at peace for the first time since the end of World War II. But dangers lurk behind the great promise of East Asia and need wise management. The dangers are not imminent. They lie just over the horizon.

They arise from the shifting balance between the four major powers — the United States, Japan, China and Russia — whose interests intersect in East Asia. Will this equilibrium alter gradually over the next decades, or will there be precipitate changes?

Historical suspicions and rivalries between Asian nations were held in abeyance by the contest between the two super powers during the Cold War. They can quickly come to the fore again if there are sudden lurches in the regional power balance. The future of the US security presence and commitments will be the key.

If America is seen to be reducing its military forces too fast or losing its will to be a major player, it is likely that there will be new arms races and tensions between the main Asian powers, and new pressures on the smaller countries in the region.

China aspires to a large role in Asia as it rapidly gains economic power and upgrades its armed forces. The Japanese government watches this with unease that can turn into alarm and lead to rearmament if it loses confidence in the will or ability of the United States to protect Japan.

The joker in the pack, a North Korean nuclear bomb, can also push Japan toward an independent defense policy that would alarm other Asians. A sudden shift in the power balance would also increase the risk of conflict at potential flash points. What can be done to reduce the risks? First, there is a clear need for more multilateral political and security discussions to build trust and cooperation. Second, the main potential cause of destabilizing change, a US military withdrawal that is too fast, must be avoided.