After World War Ⅱ, ”Japan as No.1 (or 'economical miracle'),” which signifies Japan's political and economical achievements, always attracted researchers' curiosity. As we know, politicians and bureaucrats play leading roles in Japanese political processes; consequently, the Japanese academia argued over the perspectives of ”bureaucracy domination” and ”party domination,” then the argument was switched to ”policy domination,” which emphasizes the cooperation between politicians and bureaucrats. In this article, we will discuss three perspectives mentioned previously and analyze both contexts and limitations to understand how the Japanese politics works.