Sentence:  I am prepared to demonstrate at an ytime that it represents the spirit of Imperial Russia in its most vulgar , infantile , and reactionary aspect ; that its persistent use by ballet companies of the Soviet regime indicates that that old spirit <WSD>is</WSD> just as stultifying alive today as it ever was ; that its presentation in this country is part of a capitalist plot to boobify the American people ; that its choreography is undistinguished and its score a shapeless assemblage of self-plagiarisms . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)