Yup. Japan was rightfully ours to invade; the Soviets didn't declare war on Japan until the last moment (Aug 8th, 1945?). But they wanted to carve Japan up for themselves. When we dropped the bomb on Japan, the Soviets moved into Manchuria and Korea (and took the Kurile Islands), taking them away from Japan. Roosevelt gave all that and eastern Europe to the Soviets in the Yalta Conference without getting much from the Soviets in return. To bad Patton wasn't listened to, as we could have held the Soviets back by dangling the nuclear option.
they had always wanted the contested sahkalin islands.