Japan's alliance with the United States remains the cornerstone of the country's security policy. Indeed, the alliance has long delivered Japan considerable strategic advantages, such as greater deterrence of regional security threats. Yet the alliance has also come with costs. It has institutionalized Tokyo's dependence on Washington, thus limiting the country's strategic autonomy. This chapter examines how Japan has sought to manage the task of reconciling such tensions— between the often-conflicting goals of deterrence and autonomy. It argues that, while Japan has pursued autonomy where possible, it has repeatedly prioritized deterrence as the country's primary national security goal.

Introduction

Japan's alliance with the United States remains the cornerstone of the country's defense seventy years after the original security treaty was signed by Prime Minister Yoshida Shigeru in September 1951. Why has Japan clung so close to the United States? The alliance has always delivered Japan considerable strategic advantages, notably a security guarantee and an opportunity to “underproduce” on defense. But there have also been costs. It has left Japan with a perpetual fear of either abandonment by the US or entrapment in US policies and institutionalized in Tokyo a high level of strategic dependence on Washington. For international relations theory, Japan's partnership with the US therefore raises some fundamental questions of alliance management. When managing alliances, how do states weigh up different costs and benefits and reconcile competing and sometimes contradictory national objectives?

In examining the history of Japan's alliance management, this chapter focuses on the challenges Japan has faced in reconciling in its commitment to two, at times competing, national strategic objectives: the pursuit of autonomy and deterrence. Autonomy—the capacity to act freely in international affairs—is often viewed as a key national policy goal, along with status and prestige, and has been widely examined in relation to Japan. Deterrence is widely seen as a core justification for alliances. Where states seek to balance against or deter perceived threats, they have two choices: to do so internally (via military buildups) or externally (by forming alliances).