Sentence:  Against such a termination of human life on earth by human action , he then proposes as an alternative that we `` negotiate at once with the Russians and get the best terms which <WSD>are</WSD> available '' , that we deliberately `` negotiate from comparative weakness '' . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)