Prime Minister Shinzo Abe, in a policy speech in his first regular Diet session as prime minister, pitched his top political goal -- changing Japan's postwar regime and revising the Constitution. But just what kind of nation he wants to build through such endeavors is not necessarily clear. In the short run, he apparently is trying to make constitutional revision an issue of contention in the July Upper House election campaign, in which a fierce battle is expected between his Liberal Democratic Party and the opposition Democratic Party of Japan.