One might say because as opposed to despite?

Also Germany. At the end of WWII, Germany was bombed out, whole cities were flattened. 20 years later (according to my mom who lived there in the early 60s), you couldn't even tell a massive war had ever taken place there. Some of that was the Marshall Plan providing funding, but the rest was a society that actually pulled together and got stuff done instead of being mired in corruption or infighting. Japan was largely the same way. Meanwhile, 80 years later, America can't even keep its bridges from falling down.

There is a big difference in the intervention made by US in east asian countries, and the interventions made by superpowers in other countries.

I'm not saying that South Korea and Japan didn't make good use of this intervention, but while the intervention in those countries was more akin to a financing/investment, which was in line with US' Marshall Plan during the Cold War.

In other countries such as those from Africa/South America, it was direct exploration of people and resources without really giving something back.

Intervention without exploitation would seem to be a simple-yet-fulfilling answer. South Korea received investment instead of being ransacked for resources.