I don't understand what you're saying here. First, yep, countries act in self-interest. There's no war in the history of the planet that was started out of the kindness of one's heart. That doesn't mean that the outcome of a self-interested intervention can't be just or good for the country in the long haul. I don't know how this one will pan out, but I suspect that the interests of the US and of the citizens of Venezuela are aligned much more closely than, say, in the Middle East.

Second, you're portraying US as a malicious actor operating in a vacuum. The reality is that there's a fierce competition between superpowers to broaden their spheres of influence and ultimately control the world. There's no future in which a relatively small, resource-rich, and politically dysfunctional country is left to its own devices. The choice is between Russia, China, and the US. Venezuela was more or less one of the Russian client states, and that status quo was maintained through undemocratic means, including mass murder of political opponents using the military gear provided by RU. Now, the US is going to try its hand, probably in a far less brutal way.