As I began reading Michael Yahuda’s invaluable new book, Shinzo Abe, Japan’s prime minister, declared that his country would shoot down any foreign aircraft, including drones, that entered its airspace and refused to leave. A Chinese spokesman warned that this would be seen as “an act of war and China will take resolute measures to strike back”.

Yahuda, the leading academic authority on the foreign relations of East Asia, considers the region’s two major powers as they appear to teeter on the edge of war, and what he offers is a model of clear exposition and analytic power. His publisher, however, rather undersells this thoughtful, well-documented explanation of a major regional crisis by referring to it as a textbook.

He takes us even-handedly through the history of the relations between China and Japan. Despite much threatening language from an increasingly nationalistic Beijing, the emphasis in Chinese schools on Japanese atrocities during the Second World War, together with sporadic collisions in disputed waters between both powers, and flare‑ups “likely to get worse”, Yahuda concludes that “neither [side] seeks open warfare and it seems that longer-term peaceful coexistence between China and Japan is the more likely outcome”.

Before Japan’s attack on China in the early 1930s, and its many war crimes there, thoughtful Chinese saw Japan as an inspiration for their nation’s modernisation. Even after the Second Sino-Japanese War, when Japanese security was guaranteed by the US, Mao Zedong regarded Japan as a “potential major ally against the Soviet Union”. After a long period of economic cooperation between a far less advanced China and Japan, the world’s second economic power, the balance shifted. Japan is now in decline, while China nears superpower status.

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The present crisis, highlighted by threats and counter-threats, centres on the East China Sea, which China seeks to traverse in order to enter the Western Pacific. Tokyo fears that China, intending to move from the “near seas” to the “far seas”, could encroach on its long-time trade routes, while Beijing, new to ocean-going policies and actions governed by international laws, condemns them as expressions of Western imperialism. In Japan, where it remains difficult to admit its wartime depredations in China, Beijing is now viewed as a bully and possible threat.

One of the major reasons for the new focus on maritime matters and on discord between Tokyo and Beijing was the end of the Cold War. Japan and China no longer feared Soviet threats to the region. As Japan’s power declined and China’s grew, despite their mutual need for economic interdependence, each side appeared to confront the other. This raised a weighty consideration for China: “To what extent would the United States assist Japan in the event of military clashes with China in the East China Sea, when the United States was seeking to cooperate with China in many areas of vital American interests?”

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For years, Yahuda has been on good terms with Chinese and Japanese intellectuals and security officials. He uses these contacts, probably unmatched by those of any other Western scholar, to great advantage. In both countries he asks: “Has the balance between China as a great power and as a developing country changed?” He finds the Chinese “uncertain about how best to adapt to their new ascendancy”, while the “Japanese were divided about how to manage the consequences of their decline”. For Yahuda, the outcome must be this: “China and Japan, as the two tigers of Northeast Asia, will have to learn how to share the same mountain.”