Brantly Womack has written a tour de force with the publication of China and Vietnam: The politics of asymmetry. Womack's purpose is to address a lacuna in the field of international relations by developing a theory of asymmetry to explain interactions between large powerful states and smaller weaker ones. Womack has constructed his theory from the bottom up by a detailed investigation of China–Vietnam relations from the pre-imperial period until 2006. Womack focuses his analysis on the structural aspects of the relationship and does not claim to present a full-blown historical account

China and Vietnam is divided into two parts preceded by a general overview. Part one considers the basic structure of the relationship. Womack devotes two chapters, one each to China and Vietnam, presenting what he terms the basic parameters available to each state. In China's case these include: size, centricity and localism, resource sufficiency, the challenge of sustenance and history. In Vietnam's case its basic parameters include: geography, nationalism and cosmopolitism, resource imbalance, integration and diversity, and history. These two chapters provide the basis for chapter 4 that presents Womack's theory of asymmetry.

Womack argues that ‘disparities in capacities create systemic differences in interests and perspectives between stronger and weaker sides’ (p. 17). The larger power always looms more importantly to the weaker than the reverse. This structural factor results in over-attention to the bilateral relationship on the part of the weaker state because more is at risk. Conversely, the stronger power is less attentive to the details of its bilateral relationship with a weaker state, a condition that Womack describes as the politics of inattention. The contrasting outlook of weak and strong states often leads to misperception and conflict.

Womack then introduces the concepts of stalemate, normalisation and the management of asymmetry to round out his theory. When both sides realise that they cannot prevail, stalemate sets in. When stalemated relations become routine, normalisation of relations becomes possible by careful management by both sides. The stronger recognises the autonomy of the weaker, and the weaker gives deference to the power of the stronger.

In part two, Womack examines the structure of asymmetry in seven historically structured chapters. He provides a different characterisation for each period: amorphous, internal, subjugated, role, disjunctive, distracted, dependent, hostile and normalised asymmetry. To take one example, Womack argues that Sino–Vietnamese hostility over Cambodia in the 1980s (which he terms ‘hostile asymmetry’) led to a stalemate when both sides realised that they could not prevail. This led to a period of negotiated normalisation (1990–99) in which both parties came to recognise and accept the interests of the other.

Normalcy, according to Womack, does not alter the asymmetric nature of relations; it ushers in a new phase that he terms normal or mature asymmetry. According to Womack, ‘[n]ormalcy might be called “mature asymmetry” because it is grounded in a learning experience and it has the capacity to be long term and stable’ (p. 212). In other words, both parties adopt mutual expectations of the other's behaviour. The stronger expects deference, while the weaker expects acknowledgment of its autonomy.

Mature asymmetric relations are kept peaceful by careful management by both parties. Womack identifies a number of methods to manage bilateral relations (pp. 89–90). One method is to rely on past precedent to shape common expectations of how the relationship should proceed. Another method is through ‘diplomatic ritual’, or the exchange of high-level delegations, through which each party reassures the other. The weaker defers to the powerful and the powerful accepts the autonomy of the weaker.

A third method for managing bilateral relations is to remove contentious issues from the political front burner. This can be done by reformulating the issue in dispute in order to stress common interests. For example, territorial disputes can be reformulated as a border-control issue designed to promote trade. Alternatively, contentious issues can be relegated to the purview of specialist working groups for resolution. Both parties can also buffer their relations through common membership in multilateral associations and adherence to international agreements. The weaker party also has the options of joining other smaller states in a regional organisation or allying with a third party.

Is mature asymmetry the end state for powerful and weak states in an asymmetric relationship? Womack considers the possibility of change in his concluding chapter but argues ‘[t]he overall conclusion is that normalcy is remarkably stable’ (p. 256). Current friction in the South China Sea between Vietnam and China will test this proposition.