Despite the successes of the racial middle ground, the reasons that led to its creation also led to its demise. Lashes of school segregations and Gentlemen's Agreements were bound to leave some scars on the Japanese image of the United States. More than anything else, the California Crisis exposed the hypocrisy of the American racial system and Japanese observers of the events slowly began to call into question the legitimacy of the American model.

The end of the negotiation zone between Japan and the United States was neither abrupt nor unexpected, but was a process that culminated into one event, the Paris Peace Conference of 1919. Signs of discontent were, of course, already visible years prior to the peace settlement. First, the California Crisis was far from over. The Gentlemen's Agreement had temporarily calmed minds about the immigration issue in the United States, but it did not solve the problem of the Japanese presence on American soil. Second, there was a growing feeling of irritation on part of the Japanese for being continuously relegated to the rank of a second-rate nation. Third, the loss of prestige of the American model in Japanese eyes was part of the global collapse of the Eurocentric model as a whole: the First World War as well as ravenous Western imperialism led individuals in non-European nations to reconsider the legitimacy of Eurocentrism. This occurred in Japan too, where thinkers began to explore alternative world views. The combination of these factors eventually led to the collapse of the racial middle ground.

The crisis goes on: the Alien Land Law of 1913

Two aspects of the middle ground have been emphasised throughout this work: human agency and cooperation. Two parties agree that a negotiation zone is mutually beneficial, and agents act in a framework that is acceptable for both to produce such a zone. ‘Beneficial’ and ‘acceptable’ are key. Since the inception of the middle ground described in these pages, the Japanese government had been accepting the Western framework because it proved beneficial for the nation: the preservation of national sovereignty, the possible acceptance as a great power, and, theoretically, avoiding the shame of being branded as an unwanted race – all these expectations were somewhat realistic after Japan had reached the standard of civilisation.

Yet the task of creating and maintaining the middle ground was an arduous and long process that spanned several decades.