Sentence:  The secretary 's greatest achievement is perhaps the rekindling of NATO realization that East-West friction , wherever it take place around the globe , <WSD>is</WSD> in essence the general conflict between two entirely different societies , and must be treated as such without regard to geographical distance or lack of apparent connection . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)