Once upon a time, the USSR quit the UN Security Council in protest over something or other. China's seat was held by Taiwan at the time, so we wound up with a

Once upon a time, the USSR quit the UN Security Council in protest over something or other. China's seat was held by Taiwan at the time, so we wound up with a UN-endorsed anti-communist war in Korea despite China and Russia both being actually communist. They rejoined the Security Council after that.