Pacifism or Passing the Buck?: Testing Theories of Japanese Security Policy

For decades, scholars have pointed to Japan as proof that countries can opt out of the violent world of realpolitik. Constructivist scholars in particular argue that the "culture of antimilitarism" that developed in Japan after its surrender in World War II led it to adopt a highly restrained foreign policy and to forswear the development of offensive military forces. Japan's postwar behavior, these scholars argue, demonstrates the potential for domestic politics and norms to determine a state's security policy; it also underscores the salience of constructivist theory in international politics.¹

On the surface these claims appear strong. Japanese society is imbued with pacifist norms. Despite the predictions of realist scholars that Japan will eventually behave as a "normal" great power, Tokyo has continued to show great restraint.² But is there evidence that Japan's antimilitarist norms actually constrain its security policy? What other explanations can account for Japanese restraint? What theories best explain both the continuities and changes in Japanese policy since World War II, and what should scholars and policymakers expect from Japan in the future? To answer these questions, this article outlines and tests two competing theories of Japanese security policy: a constructivist theory of antimilitarism and a realist theory of buck-passing.

This article makes three central arguments. First, the debate about the roots of Japanese security policy suffers from widespread misunderstanding about a fundamental aspect of that policy: the level of Japanese military power. Scholars either have neglected to measure Japanese military power or have measured it superficially, fueling the misconception of Japan as a "military pygmy."³ Japan, however, is no military pygmy; over the course of the Cold War, Japan transformed itself from a burned-out ruin to one of the world's foremost military powers. Second, a constructivist theory of antimilitarism, which expects domestic norms to inhibit major changes in Japanese security policy, cannot account for this dramatic transformation. Third, the conduct of Japan's post-World War II security policy—both the period of meager defense effort and the period of vigorous military buildup—is consistent with a realist strategy of buck-passing.

This analysis has implications for international relations theory and for U.S. foreign policy. Constructivists have persuasively demonstrated that antimilitarist norms pervade Japanese society, and scholars have held up Japan as one of the key examples of domestic norms overriding the influence of the international system and driving a state's security policy. The failure of antimilitarist norms to restrain Japan casts doubt on their effect on foreign and security policies elsewhere. As for U.S. foreign policy, this article suggests that as long as Japan continues to follow a strategy of buck-passing, the United States will have difficulty convincing Japan to increase its contributions to the alliance. Historically, Tokyo has not significantly expanded its defense commitments as a result of American urgings, but rather when the U.S. commitment to the region appeared to wane.

This article is not a general attack on constructivism; nor does it purport to test constructivism or realism. Constructivism and realism are paradigms; they are impossible to falsify because each includes a family of contradictory theories.⁴ Rather than attempt to "test" paradigms, this study tests two specific explanations for Japanese security policy since World War II, with the goal of building a better foundation for predictions about future Japanese policy.

The remainder of this article is divided into four main sections. The first section dispels the myth of Japan's military weakness. It argues that Japan has far more military power than most analyses suggest. The second and third sections summarize realist and constructivist theories for Japanese security policy, infer predictions from these theories, and evaluate these predictions against historical data from Japanese policy since World War II. The fourth section addresses possible counterarguments.

Japanese Military Might

Most analyses of Japanese security policy greatly underestimate Japanese military power...