The brutal past exists in Europe as well. Portugal had a colonial war up to 1974 with records of mass executions in Africa. Franco's Spain had it's own dark history with mass graves still being uncovered. Franco' regime ended even later and the country still has staunch Franco supporters.
Do you not consider Salazar or Franco's regime up to par to South Korea? If not what is the criteria?
Also to answer the other comment, Russia has repeatedly toyed with the idea of a nuclear bombing to Warsaw as well as invading the baltic. The baltic states are more than within range for a ground invasion. Poland has a border with the Kaliningrad enclave as well. Now you might say, that Russia would not dare... Well ask any baltic state how scared shitless they were with how easy Russia imposed itself on Ukraine. I honestly do not see how Korea is in a much different scenario.
Also to answer the other comment, Russia has repeatedly toyed with the idea of a nuclear bombing to Warsaw as well as invading the baltic. The baltic states are more than within range for a ground invasion. Poland has a border with the Kaliningrad enclave as well. Now you might say, that Russia would not dare... Well ask any baltic state how scared shitless they were with how easy Russia imposed itself on Ukraine. I honestly do not see how Korea is in a much different scenario.