Japan is on the verge of what would be a dramatic shift in defense posture. The ‘spear and shield’ structure of the US–Japan alliance, at the center of its security policy for most of the postwar era, is being revamped by a move toward autonomous defense. Why would a country confined to a largely passive and Americanocentrist posture for more than half a century suddenly change course? I argue that autonomy is for Japan the only way out of an unprecedented ‘entrapment-abandonment dilemma’: any attempt to prevent defection by the United States in the face of an increasingly assertive China heightens to an unacceptable level the risk of Japan being dragged into a US-led conflict in the Korean Peninsula, and vice versa. Japan’s ability to wield the spear would likely have destabilizing consequences for the whole Asia-Pacific region.
International Relations of the Asia-Pacific: https://academic.oup.com/irap/advance-article-abstract/doi/10.1093/irap/lcy006/4959342?redirectedFrom=fulltext