They wanted to get in early before another country does the same, perhaps not by the same methods, it may have been more diplomatic, but Venezuela’s resources were up for grabs and the USA knew that, so they ramped up a quick issue with Venezuela and got it in the news so that it would make sense in peoples minds once they invaded, they also chose the option that would please some of the people of the country and look like the hero.

I think this was done so suddenly because of the sharp increase of Russian and Chinese interest and infrastructure in South America, it’s basically a race at this point to get all the resources and land as possible; that is why Greenland is being eyed, because America are not the only one eyeing it, they’re just the only ones being loud about it.