I know this might break the 20 year rule, but there are some aspects that don't break the rule. Basically if this breaks the rule I understand. Basically the US was good at rebuilding Western Europe after WW2, they rebuild Japan after WW2, rebuilt South Korea after the Korean War, (debatably) rebuilt South Vietnam after the Vietnam War, but after that we just sucked at rebuilding and got more hate than results in rebuilding the nations we were trying to help. Is there a reason for this?
We didn't "rebuild" most of the nation's you are talking about. Japan was given money and some aid but their government was not largely placed or influenced by us. We didn't "rebuild" Vietnam either, South Korea was given aid but they already had a political and economic idea that was going to thrive. Infact we couldn't bother rebuilding Japan with the United states just coming out of a terrible economic down turn then a war. The nation didn't go back to everything being what people think of the economic power we were till we just did it quicker.