HE KNEW HE WAS RIGHT.

Until not long ago, Christopher Hitchens, the British-born journalist, was a valued asset of the American left: an intellectual willing to show his teeth in the cause of righteousness. Today, Hitchens supports the Iraq war and is contemptuous of those who do not--a turn that has confused and dismayed former comrades, and brought him into odd new alliances. But his life looks much the same. He still writes a great deal, at a speed at which most people read. And, at fifty-seven, he still has an arrest-photograph air about him--looking like someone who, with as much dignity as possible, has smoothed his hair and straightened his collar after knocking the helmet off a policeman.

At a dinner a few months ago in San Francisco with his wife, Carol Blue, and some others, Hitchens wore a pale jacket and a shirt unbuttoned far enough to hint at what one ex-girlfriend has called "the pelt of the Hitch." Hitchens, who only recently gave up the habit of smoking in the shower, was working through a pack of cigarettes while talking to two women at his end of the table: a Stanford doctor in her early thirties whom he'd met once before, and a friend of hers, a librarian. He spoke with wit and eloquence about Iranian politics and what he saw as the unnecessary handsomeness of Gavin Newsom, the mayor of San Francisco.

Hitchens writes on politics and literature; and in both lines of work he tends to start from textual readings of a subtle and suspicious-minded kind. When he is not writing, he talks in the same measured, ironic voice as his prose, with the same fluency and intellectual momentum, as if he were troubled by the thought that he might never find another audience. Hitchens likes to have his say: he takes his arguments to the cable-news channels, to West Point cadets, to panel discussions in windowless hotel conference rooms. He stays at public meetings until the crowd--dehydrated and faint--has no more questions to ask, and then he gives out his e-mail address. He is a fine, funny orator, with the mock-heroic manner of an English barrister sure of his ground ("by all means," "if you will"), using derision, a grand diction, and looping subclauses that always carry him back to the main path. He also has the politician's trick of eliding the last word of one sentence to the first of the next, while stressing both words, in order to close a gate against interruption. In more private settings, the rhetoric is the same--except that there are filthy jokes drawn out to twenty minutes, and longer quotations from his vast stock of remembered English poetry. He seems to be perpetually auditioning for the role of best man. Ian McEwan, the novelist, recently said of Hitchens, "It all seems instantly, neurologically available: everything he's ever read, everyone he's ever met, every story he's ever heard."

In the noisy front room of the North Beach restaurant where the friends had met, Hitchens made a toast: "To the Constitution of the United States, and confusion to its enemies!" The conversation was amiable and boozy; Hitchens might be said to care more for history than for individual humans, but he was in an easy mood, after a drive, in beautiful early-evening light, from Menlo Park. (He and Blue, a writer working on a novel, live with their thirteen-year-old daughter in Washington, D.C., but spend the summer in California, where her parents live.) During the ride, he had discussed with the Pakistani-born taxi-driver the virtues and vices of Benazir Bhutto, while surreptitiously using a bottle of Evian to put out a small but smoky fire that he had set in the ashtray.

And then the young doctor to his left made a passing but sympathetic remark about Howard Dean, the 2004 Presidential candidate; she said that he had been unfairly treated in the American media. Hitchens, in the clear, helpful voice one might use to give street directions, replied that Dean was "a raving nut bag," and then corrected himself: "A raving, sinister, demagogic nut bag." He said, "I and a few other people saw he should be destroyed." He noted that, in 2003, Dean had given a speech at an abortion-rights gathering in which he recalled being visited, as a doctor, by a twelve-year-old who was pregnant by her father. ("You explain that to the American people who think that parental notification is a good idea," Dean said, to applause.) Dean appeared not to have referred the alleged rape to the police; he also, when pressed, admitted that the story was not, in all details, true. For Hitchens, this established that Dean was a "pathological liar."

"All politicians lie!" the women said.

"He's a doctor," Hitchens said.