Every other attempt at a different path elsewhere was undercut by military coups, invasions, economic blockades. One would hope that communism/socialism would be robust to destabilization efforts, but it was not the case. Capitalism also took time to develop, such as various attempts in the Italian city states before first taking root in Denmark. Hopefully, a new system of peace and cooperation will replace our brutal empire.
I think you're the type of person that when wrong sorta talks about a bunch of adjacent topics to try to avoid the point of admiting that you were wrong.
The Sino-Soviet bloc and the Warsaw Pact controlled roughly a third of the world's population, an immense percentage of the Earth's landmass, and practically every natural resource required for autarky. They had nuclear parity, massive industrial bases, and their own closed global trading network (COMECON). If a system with that level of geographic, demographic, and military shielding cannot sustain itself, it is not due to a lack of opportunity.
It is prima-facie absurd to claim "it just wasn't given a chance"
Simply that a type of order was enforced to build a global money-ist theory of society and and market + trade platform.
I might, wrongly, argue that many of these regions both would have continued in the chaos and death they otherwise were already participating in, but i'd also accept that the Dutch in Africa, English in the Caribbean and China, etc all introduced net new outside chaotic aspects on purpose. I'd also accept that attempts at order by the American's ultimately resulted in chaos, especially of course in the middle east.
As to south america, this I'll acknowledge of course was an history of interference, one that is hard to argue the contra-positive since communism in almost all regions of the world failed to develope a long term stable order which was both culturally, trade, and fiscally sustainable, with many falling to a worse state after these outcomes.