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In OTL, the US and PRC had a durable detente for the last 20 years of the Cold War and were in a de facto anti-Soviet coalition. This complicated the Moscow's situation quite a bit and eased Washington's and Beijing's security problems somewhat compared to the alternatives.

However, for the United States, this happened after two costly wars in which China fought America (Korea) or underwrote its enemy (Vietnam).

The very cost of those wars may have been crucial in making rapprochement with Beijing acceptable within American politics.

For the US, it might have been handy had rapprochement occurred *before* the Vietnam War, either allowing America to "win" the war (preserve a separate South Vietnam) or allowing America to not engage and allow Communst takeover of the south without caring or feeling like its a loser because of it.

Can you sketch out a scenario where this happens? Is it even plausible?
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