Korea was a UN sanctioned intervention and in retrospect kept the Chinese and Russian expansionists contained. Had there not been an intervention, much of Asia as we know it today would have Laos style systems.
In respect to the Europeans, they are not in a position to criticize anyone. The history of Portugal and France in Africa is disgraceful. France looted Haiti of every asset it had. Is it any wonder that Haiti has been a basket case since? Spain's legacy of foreign meddling and support of right wing dictatorships makes the USA of the 1950's look moderate in comparison. The Germans, Italians and Japanese fondness for commercial bribery made the mafia look tame in comparison. The UK's shenanigans in the Gulf post WWII made the USA look angelic in comparison. The Europeans killed off the natives in the Caribbean and then imported slaves. The result is the economic dependency that is the Caribbean today. Italy and France left a mess in North Africa, a mess for which they never took responsibility. The treatment Spain and Italy give refugees makes the US treatment of Mexican border jumpers look compassionate in comparison. As for the Russians, they have had a long history of supporting the world's most barbaric dictatorships. The USA has done some wrongful acts, but it would take another century for it to come even close to the genocide and outright looting the Europeans effected over many centuries.