SINCE THE SIGNING of the peace treaty in the late summer of 1951, rearmament has assumed steadily increasing importance in Japanese politics and policy. Directly and indirectly this issue influences major political, constitutional, economic, and diplomatic problems confronting the Japanese government and the Japanese people. The creation in 1954 of a new defense establishment with land, sea, and air arms has centered Japanese attention upon concrete and current aspects of rearmament, and has caused growing concern about its future implications. In domestic politics the impact of rearmament is clearly discernible. In the 1955 elections it contributed to the spectacular fall from power of the Liberal party which had dominated Japanese politics almost without interruption since the first postwar election in 1946. A fundamental split over both the advisability and the extent of rearmament is contributing to a growing bipolarization of Japanese politics. On the one hand, the Liberal party and its successor in power the new Democratic party both favoring rearmament and representing the powerful conservative wing of Japanese politics, seem to be moving in the direction of coalition; on the other hand, the two wings of the Socialist party, at odds since 1951 but standing together in their opposition to rearmament, seem to be approaching a reconciliation. It was rearmament, too, which was at least the point of departure for a conservative attempt drastically to revise the democratic constitution; and not only to eliminate the so-called renunciation of war clause, but also seriously to modify many fundamental democratic provisions of the constitution.