How's this?
Mao Zedong is killed in the Chinese Civil War, and Zhou Enlai, with the support of Zhu De, Commander-in-Chief of the Red Army, is able to become the new head of the Communist Party. The Communists win on schedule in 1949, but Zhou Enlai lacks Mao Zedong's insanity, and thus does not hurtle the nation into crazy plans such as the Great Leap Forward; subsequently, China not only does not suffer 20,000,000+ deaths due to famine, but is able to actually industrialize (rather than concentrate on building incredibly terrible steel foundries that produce crap steel). Furthermore, Zhou is able to convince Stalin that the situation in North Korea is simply not winnable at this time; thus, Stalin does not give Kim Il Sung the green light to attack South Korea in 1949. With no Korean war, Japanese industry is unable to get off the ground, and the situation soon becomes intolerable. In the meantime, by 1955, China has fully recovered from the ravages of World War II, and its apparent success makes it the beacon of light in Asia, rather than Japan. Without the Japanese model, South Korea is also unable to overcome the losses of World War II, while North Korea, kept fed by Soviet and Chinese aid, quickly improves its living conditions, surpassing the South. Although China has "gone red," the calm and security of Asia, combined with the American (in fact, Western) racism against Asians, makes Americans feel more secure about the situation in Asia, and concentrate more on the situations in Europe.
The Soviet boycott of the UN over Taiwan's being seated in the Security Council instead of mainland China ends by 1952. Furthermore, de Gaulle becomes President of France in 1958, and begins his attacks on the power of America and calls for a European Europe. It is in this political atmosphere that Zhou finally feels that the situation is right, and gains Khruschev's support in giving Kim Il Sung the weapons, supplies, and permission to attack. On May 1st 1961, May Day, the radical workers' holiday, North Korea launches a surprise attack on South Korea, quickly penetrating S. Korean defenses and taking the capital city of Seoul. The US' efforts at bringing a UN intervention is vetoed out of hand by the Soviet Union, which calls the war a revolution by the Korean people and thus a "wholly internal matter." de Gaulle also refuses any attempt at NATO intervention, saying, quite bluntly, that he will not spend French lives to save Korean ones. Thus, by the time the United States decides to intervene on its own, the Korean peninsula is completely lost, and the People's Republic of United Korea is proclaimed.
The embarassment in Korea is the last straw; the Americans are generally discredited in Asia, as the Japanese economy is still a bare shadow of what it was before World War II, while China has now become the fourth economic power in the world, behind the United States, USSR, and the UK. Japanese communists win more and more elections in the country. The US responds by increasing its troop strength in Japan, to ward off any attempted Sino-Soviet attempts at an "uprising," and involves itself heavier as Vietnam continues to flare up, including a full-on invasion of neighboring Laos, which is proven to allow Vietnamese incursions across their border.
When Zhou dies in 1976, his successor, the able and resourceful Deng Xiaoping, continues Zhou's foreign policies, which include supplying the communists of Vietnam, who are still fighting against the American giant. America finally withdraws from Vietnam in 1978, but has so heavily damaged North Vietnam that South Vietnam does not crumble. Thus, also the US reputation is damaged at home and the youth movement does not falter in the 1980s, the US stands proud that it succeeded in Vietnam, though at the cost of nearly a hundred thousand American lives. By the end of Zhou Enlai's life, the Soviet Union and the PRC were beginning to go their different ways, as Moscow's attempt to insert its will across Asia were stymied by Beijing; when Deng Xiaoping came to power, he expanded upon the forms of capitalism that had been introduced by Zhou Enlai, which drove the USSR further away and propelled the Chinese economy to overtake Britain's in 1979. Although no Sino-Soviet war erupted, the loss of China as a true ally meant a weakening of the Soviet Union. To prove that they were not like the Americans, the Soviets entered Afghanistan, only to find it as deadly to them as Vietnam had proven to the US. The Soviet Union finally collapsed in 1991, after a failed coup against Mikhail Gorbachev, who had attempted to bring Deng's reforms to the USSR with added freedoms.
With the Soviet Union failed and gone, the People's Republic of China, the most ancient and populous nation on Earth, now led international Communism against the capitalist tide!