Can Asia-Pacific security vacuum really be filled?

Denny Roy looks at whether the prospective vacuum created in the Asia-Pacific in the wake of a U.S. military withdrawal will actually be filled by another power.

The assumption that a withdrawal of U.S. influence from the Asia-Pacific would create a power or security "vacuum" has become commonplace among analysts of the region. This assumption, however, has been largely unexamined. The "vacuum" metaphor implies that if the dominant power, or hegemony, abdicates its role as shaper and enforcer of the rules of international interaction, the forces of nature will immediately and inevitably suck another country into this role as a replacement.

But the "vacuum" effect is only one possible response to the diminution of great power influence. While the emergence of a power vacuum in the region is a strong possibility, this outcome is not inevitable. History bears out this conclusion.

After the First World War, Great Britain was clearly finished as the world's dominant power. No other major European power was in any position to take up global leadership. Two rising powers reacted in opposite ways to this hegemonic breakdown. In the Pacific, Japan, which had previously cooperated with the dominant power (and would return to this pattern again after World War II), opted to build its own regional hegemony, the Greater East Asia Co-prosperity Sphere. But the U.S., by then the world's strongest power (although militarily under-armed), declined the global leadership role of which it was capable.

There was no "vacuum". The vulnerable Japanese decided to take control of an uncertain and threatening external environment, but the Americans, militarily secure and economically almost self- sufficient, saw no compelling reason to strive for hegemony.

The reason the "power vacuum" is not a sure thing is that rising, middle-rank countries have both incentives and disincentives for opportunistic expansion. One incentive is control of the international or regional system, which the dominant power can adjust to serve its own interests. Another incentive is defensive: blocking a neighboring state (and potential enemy) from gaining additional capabilities and privileges that would result in an increase of its relative power.

These incentives, however, are potentially balanced by countervailing considerations. A state that suddenly becomes more assertive will frighten its neighbors, which will likely respond by forming an alliance to contain the threatening state. Another disincentive to unilateral expansion is economic interdependence: peaceful cooperation may be a more effective way to amass national wealth than coercion and conquest. In theory, then, a rough balance obtains between the factors that would give rise to a vacuum and the factors that would prevent a vacuum.

Moving from the abstract to the concrete, do the particular characteristics of the Asia-Pacific region make it susceptible to the vacuum effect? There are two bright spots. First, the smaller states of the region have become stronger since the Japanese invasion of the Pacific War. These states are now better able to protect themselves and to contribute resources to a defensive alliance. Second, ASEAN has proved it can foster cooperation and dialogue for Southeast Asian states.

But conditions that would guarantee peace and stability in a post-hegemonic environment do not yet exist. Northeast Asia has no real counterpart to ASEAN, and the establishment of effective multilateral organizations faces the serious obstacles of historical animosity (Chinese versus Japanese, Japanese versus Koreans, North Koreans versus South Koreans, and so on) and seemingly insoluble political grievances (divided Korea, divided China, disputed territories, and so forth).

Economic interdependence in the region is uneven; the major ties are bilateral connections between Japan and everyone else, and states trade more with outside countries than among themselves.

Only the Russians and the Chinese have nuclear weapons, further skewing the imbalance between the strong and the weak states, and creating the potential for nuclear blackmail should the U.S. nuclear umbrella be removed.

Political systems throughout the region remain highly dissimilar, running the gamut from democracy to hard-core authoritarianism. While Japan is clearly content with the status quo and would not undertake a major military buildup unless provoked, the same cannot be confidently said of China.

Thus, while the vacuum effect is not inevitable here, it will remain the most likely outcome unless purposeful action is taken to avoid it. Regional states would be wise to use this decade or so of breathing space to strengthen the disincentives to opportunistic, unilateral expansion by deepening the culture of multilateralism, ingraining the habits of consultation and compromise, and avoiding steps that would increase neighbors' sense of insecurity. The ideal the region should work towards is a no-vacuum outcome in which no government suddenly increases its military capabilities or political demands in the wake of a U.S. withdrawal.

Instead, governments in the region might agree to maintain the present system of economic and political regimes, or meet together to formulate new regimes, and all would continue to pursue their interests through established diplomatic channels and peaceful economic competition.

Dr. Denny Roy is a Research Fellow at the Strategic and Defense Studies Center at the Australian National University.