Besides Rhodesia and South Africa, some other major examples are the Katanga Crisis and the Suez Crisis.
Are Nasser and Mobutu supposed to be communists in your model of history? They are not in mine.
In the latter, the U.S. effectively joined forces with the Soviet Union to support Nasser against the British and the French.
Nasser opposed communism. Sure, both American and the Soviet Union preferred a non-Europe-controlled Egypt, because they respectively preferred an America-controllled and a Soviet-controlled Egypt. What does that have to do with anti-colonialism trumping anti-communism? It wasn't a communist regime that America supported then, it was Nasser's anti-communist regime.
Look, I'm not interested in having a discussion where "communism" has been redefined to mean pretty much the entire modern world. I'm well aware that there exist some people (e.g Moldbug-type reactionaries) that believe that even modern-day America is "communist" according to their own definition, but I'm talking about ordinary definitions of "communism".
Are Nasser and Mobutu supposed to be communists in your model of history? They are not in mine.
Mobutu consolidated power only in late 1965, and there were many other relevant people involved about whose degree of affiliation with communism we could debate. (And frankly, I'm not very knowledgeable about, or particularly interested in, the details of this particular war.) The point however is that a reflexively and consistently anti-communist U.S. policy would have simply backed Tshombe and his Katangan government.
As for the Suez crisis, the point is not...
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