Cancer weakened, but did not soften Christopher Hitchens. He did not repent or forgive or ask for pity. As if granted diplomatic immunity, his mind’s eye looked plainly upon the attack and counterattack of disease and treatments that robbed him of his hair, his stamina, his speaking voice and eventually his life. “I love the imagery of struggle,” he wrote about his illness in an August 2010 essay in Vanity Fair. “I sometimes wish I were suffering in a good cause, or risking my life for the good of others, instead of just being a gravely endangered patient.” Hitchens, a...