I have read Latino demographic is now below replacement level. US is designed for where high achiever are overcompensated and any economic decline will impact latino demographic worse. This Covid did to hispanic.South American countries lack the grit to conduct asymmetric warfare in the face of an overwhelming disadvantage. In some sense, it was beaten out of them during the Cold War, as hardcore guerillas like Che Guevara and his band were hunted down & executed. But in another sense, there's just not a sufficiently powerful ideological force within South America to oppose American hegemony - they've more or less accepted it and have found a niche within it, with the eventual hope of a Latino demographic take-over of the US in place of any military resistance.
lol. how can you ignore Soft Power. which is only comes from Royal Families. Afghans of all sheds have that connections. even these Houthis who are on opposite end are saved by Oman.Contrast that with the Middle East, where despite being at even more of a disadvantage vs. Western militaries, Islamic insurgents were able to consistently pose a problem for the US military. Decades after the US began its campaign to "democratize" the Middle-East, we see the Taliban return to power in Afghanistan, and the rest of the US's "nation-building" projects descending into irrelevance. The shift to a more "use Arabs to fight Arabs" strategy, under Trump and Biden, was, in this sense, out of necessity - the US recognized that it couldn't just pull off a simple military victory.
South America is clearly not the Middle East, and expecting South Americans to fight like Arabs or even Iranians is just not practical. China's ability to guarantee security in the region is effectively zero. You can't seriously defend people who won't seriously defend themselves.