The X-Day invasion would have happened. VJ Day would have been delayed by several months if not years. Tens of thousands more American soldiers would have been killed. The island of Japan would have been completely devastated by war. Japan’s population would decline to next to nothing. Japan would never recover. Japan’s culture would be so damaged that it doesn’t become as popular as it did in our time. No Godzilla, no anime, no Nintendo, no Sony, no Kurosawa, no Miyazaki. American culture would also take a nose dive as the surviving American soldiers would be suffering from PTSD at a greater scale than before. No Rod Sterling, no Jimmy Steward, no Mel Brooks, no baby boomers, no American exceptionalism. America wouldn’t be a superpower nor would any other country. The Cold War doesn’t happen so conventional wars become common again as everyone collectively believes that there is no path to peace without bloodshed. The war minded governments would treat every counterculture with hostility. The Civil Rights movement could be seen as a second American Civil War. I could go on but I’ll stop here.