Sentence:  If our SAC bombers <WSD>were</WSD> , today , capable of surviving a surprise missile attack and because of infinite dispersion or long endurance had the capability to strike at Russia again , and again , and again , those bombers would unquestionably assure our military dominance . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)