Upon his return from an alternate reality, Trade Minister Tagomi brought back with him a new reel of the US testing the Hydrogen Bomb in the Bikini Atoll. He showed it to Chief Inspector Kido, who then traveled to the American Reich to show it to Obergruppenfuhrer Smith, who then defied orders and traveled to Berlin to show it to Nazi High Command. The news reel convinced the Nazis that the Japanese had had the time to build more and that a war would end the world. So in effect, the Hydrogen Bomb ended WWIII before it even started.
- In our timeline, the Hydrogen Bomb was tested by the United States in 1954 and by the Soviet Union in 1955. The closest the bombs came to seeing use in war was the Cuban Missile Crisis in 1962, but tensions never escalated to war.