Japan became the 69th member of the United Nations on December 18, 1956. Since then, Japan holds many international cooperations within the United Nations as a basic principle of its foreign policy.

When Japan joined the UN in 1956, it did so with great enthusiasm and broad public support, for the international organization was seen to embody the pacified country's hopes for a peaceful world order. Membership was welcomed by many Japanese who saw the UN as a guarantor of a policy of unarmed neutrality for their nation, in addition to the security arrangement they concluded with US in 1951. To others, support for the UN would be useful in masking or diluting Japan's almost total dependence on the United States for its security. The government saw the UN as an ideal arena for its risk minimizing, omnidirectional foreign policy.

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