Pesukim about shrubbery in Yeshayahu are interpreted as symbolizing Esther, Vashti, Mordechai, and Haman. Is Vashti evil? Why does she appear here? The symbolism in Yeshayahu suggests tangible, objective improvement. In addition to justice against the would-be destroyers of the Jewish people and Temple, the triumph of the righteous heroes cause an objective improvement to society at large.