Sentence:  A state ideology, mixing nationalism, and basic Marxist economics, going under the name "Juche", was constructed, and Kim Il-sung <WSD>effectively</WSD> silenced, disposed of and cleared away any opposition, isolating the country and exercising an iron grip on the military, the state media and the government and party organs. 
Meaning of the word marked with <WSD> tags:  In an efficient or effective manner; with powerful effect.