The Khmer Rouge terrorized Cambodia during the 70's when they violently took control of the country. They enforced a strict communist rule and imprisoned many Cambodians in prisons similar to those used by other Stalinist dictators. The reign of the Khmer Rouge under Pol Pot resulted in the deaths of over 1 million people and has permanently scarred the country.
Over 28 years later the leaders of the Khmer Rouge are finally being persecuted for their violent crimes. With the assistance of the UN Cambodia has captured and is now trying Khieu Samphan, Kaing Guek Eav, Leng Sary, and Nuon Chea.
I believe the cooperation between the UN and Cambodia is a step towards recognizing disasters that have occurred throughout history and ensuring they do not happen again.