The United States of America and Japan are considered to be the friendliest and closest allies in the Asia Pacific region since the end of World War II. Yet, over seven decades ago, the US and Japan were bitter and hostile enemies who fought a total war that almost exterminated each other in the most horrid ways known to humankind. Thus, how did these two historical enemies manage to shape and mold a strong political community setup from the ashes of WWII, and maintain their bilateral relations peacefully where the use of military force in international disputes has almost become unthinkable? How do former enemy nations build new peaceful relationships from their jarring experiences of war and hatred that were established and implemented by past othering institutional behaviors? My problematique begins with the vilification of the other and the caricatures of bitterness and hatred identification of evil in the other, which were utilized during war and triggered for war itself; and how reconciliation actions played a vital role to bring WWII to an end and creating the necessary conditions for building the Pluralistic Security Community (PSC) Tier-Cycle development stages. The research project intends to analyze the under-researched US-Japan reconciliation issues and offers a unique scientific understanding of reconciliation signaling and reconciliation institutionalization in international affairs. Hence, my dissertation will remedy the gaps in the literature by shedding a new light and perspective on the vital role of reconciliation, and how reconciliation actions enabled the move toward pluralistic security communities between former WWII enemy states.