Among living British novelists, Ian McEwan is widely thought to have the highest intellect and the widest frame of reference. On Chesil Beach, his latest novel (a novella, really) has been extravagantly praised for its subtle evocation of English sexual mores in 1961, on the eve of the sexual revolution. Edward and Florence—“young, educated, and both virgins”—endure the wedding night from hell. As a tragedy of manners, it is indeed faultless.

The new work is no less worthy of attention, though, for what it tells us about its author’s political evolution. Mr. McEwan’s stature as a public intellectual has grown in recent years as his views have developed from the predictable platitudes of a conventional leftist to an unconventionally robust defence of Western civilization and an equally sharp critique of Islamist designs upon it.

On Chesil Beach makes scarcely any reference to Islam, which is hardly surprising given the date. As Edward and Florence enjoy—if that is the word—a large dinner of roast beef in their hotel room for which neither has any appetite, they overhear the news on the wireless from the sitting room downstairs. Harold Macmillan is in Washington to make the case for a test-ban treaty. “Who could disagree that it was folly to go on testing H-bombs in the atmosphere and irradiating the whole planet?” the author asks. “But no one under thirty—certainly not Edward and Florence—believed that a British prime minister held much sway in global affairs.” Next they hear a story from Berlin, where refugees flee Communism just before the erection of the wall. The third “intolerable” item is “the concluding session of an Islamic conference in Baghdad.” By this time the tension between Edward and Florence has diverted their attention back to thoughts of the night ahead.

Later we are shown flashbacks that throw more light on McEwan’s politics seen through the prism of the early 1960′s. The young couple, whose political attitudes are typical of their generation, meet at a Campaign for Nuclear Disarmament event in Oxford. But Florence’s mother Violet, an Oxford philosophy don, takes a dim view of her daughter’s politics. Violet’s “objectionable” opinions about the evils of Communism include comparing the Soviet Union to Nazi Germany—a comparison that “disgusts” Florence. “She recognized in Violet’s opinions a typical pattern of pro-American propaganda. She was disappointed in her mother, and even said so.”

Violet also gives her prospective son-in-law a tutorial while he chauffeurs her to academic gatherings. Knowing his interest in medieval millenarian cults, she goads him by comparing these movements to early socialists and their apocalyptic beliefs to contemporary fear of nuclear war. Edward prefers to focus on the “difference between, on the one had, a lurid and absurd fantasy devised by a post-Iron Age mystic, then embellished by his credulous medieval equivalents, and, on the other, the rational fear of a possible and terrifying event it was in our power to prevent.” Violet responds “in tones of crisp reprimand that effectively closed the conversation.” Her point is not whether either the medieval cultists or the CND supporters were wrong, but that they sincerely believed they were right and acted accordingly. “Surely, as a historian, he had learned that down through the centuries mass delusions had common themes.”

Is it far-fetched to detect here a gentle authorial admonition—if not a warning—to the present-day equivalents of Edward and Florence? They, too, deny that a British prime minister could “hold much sway in world affairs”—which Tony Blair, and before him Margaret Thatcher, have palpably done. They, too, prefer to ignore the latter-day manifestations of tyranny around them—whether Communist or Islamist. They, too, object to talk of “Islamofascism” and comparisons with the Nazis, which they dismiss as “pro-American propaganda.” They, too, attend mass protests against the Iraq war and other aspects of U.S. or British foreign policy, but refuse to countenance any suggestion that these rallies might have anything in common with “mass delusions,” Islamist or otherwise. True: Edward takes a side-swipe at Jesus—McEwan’s hostility to Christianity has been widely noted—but the author has Islam in his sights at least as much as Christianity.

These few passages I have quoted are by no means the most powerful or important in the book, but they are enough to suggest that McEwan is by no means resiling from his tough pronouncements in articles and interviews. Just how unusual his stance is among British writers may be surmised from an interview given last week to the Berliner Zeitung by the Scottish novelist A.L. Kennedy, who compared Britain under Blair to Germany under Hitler. There was not a trace of humor in her remarks, which equated the fate of Muslims in present-day Bradford or Birmingham to that of Jews in the Holocaust.

At least McEwan, describing Edward’s later life, has him repudiate his former view that “everyone knew that [the press] was controlled by state, military, or financial interests.” It takes courage to admit that one has been wrong about politics—and courage is a virtue that seems to be in singularly short supply among British writers just now.