Japan went first, going along with Bidens sanctions
Biden had no sanctions.
No real ones.
C’mon. The Russians weren’t going to give them back, anyway. Absent some gigantic bribe or concession from Japan.
In the spring and early summer of 1945, the main Japanese diplomats put their faith in the Soviets to mediate with the allied powers and soften the demands of the Potsdam conference. At the last minute, when everything was falling apart, nuclear bombs were falling and the Japanese had not heard from the Soviet diplomat in days, they finally got through to him. He listened for a few seconds to their desperate pleas, then cut them off by telling them the Soviet Union was declaring war on them! It goes to show what happens when you rely on diplomacy combined with weakness.