For people under thirty, Eminem may be the most significant recording artist in the English-speaking world. His previous album, “The Eminem Show,” sold eight million copies in a little under a year. (The Beastie Boys’ “Licensed to Ill,” an equally politically incorrect though vastly superior record by equally white rappers, took twelve years to sell that many copies.) Eminem’s new album, “Encore,” has sold more than a million and a half copies in less than two weeks. And, terminally unpleasant or not, Eminem is occasionally astonishing, able to upend expectations and redeem his many tedious attempts to épater all of us.

Perhaps aware that shock inevitably produces its own tedium, Eminem talks in the current issue of Rolling Stone about his eight-year-old daughter, Hailie, and the difficulty of co-parenting her with his ex-wife, Kim Mathers, who has attempted suicide and was jailed earlier this year for drug possession. The article includes a discussion of Eminem’s new sense of maturity.

Little of this offstage thoughtfulness can be found in “Encore” ’s seventy-seven minutes of superstar petulance, bathroom jokes, misogynism, and simple lazy-assedness. Because Eminem’s songs are rooted in adolescent anger and its paper-thin rationalizations, they must deliver big to justify an essentially annoying world view, either with aesthetic fireworks or with a performance convincing enough to distract us from the artist’s bottomless ability to feel sorry for himself. He has done it in the past with “Lose Yourself” and “Stan,” close-to-perfect songs that help explain his critical lionization.

One of Eminem’s best songs was his 1997 début single, “My Name Is,” produced by his mentor and sponsor, Dr. Dre. The electric-piano sample is deceptively cheerful, just the right camouflage for an unknown white rapper from Detroit gleefully tipping over sacred cows in this confident, deadpan whine. Why did he want to impregnate pop stars and hang himself and insult his mother? At first, we didn’t need to know. His rhymes were organic pieces of a perfectly pitched, if amoral, comedy. Eminem was smart enough to smile when complaining, a balance some songwriters never learn. For instance, when he was discussing the challenges of new fame, on 1999’s “The Real Slim Shady,” the beats and the words collided in a happily constrained way, like marbles being shaken in a jar. He had developed his own style, creating unusually long concatenations by inserting different words into the same rhythmic pattern over and over. (In the wrong hands, this method mimics a child’s repetitive “Mom? Mom? Mom?”) When Eminem’s rhymes click, they feel both musically calibrated and lexically tuned, the careful work of someone who loves language and has crumpled up a lot of paper trying to figure out how, and where, words fit together.

But on “The Eminem Show,” his third major-label album, Eminem’s scansion was being squashed by his personality. No longer the underdog, he sounded like Al Pacino in “Scarface,” paranoid and entitled. The humor had curdled. Eminem no longer wanted to hang himself; it was you and everyone else he was after. The beats became slow and flat, losing syncopation as the air left the room.

On “Encore,” his fourth album, the rhythms have hardened into a martial clomp that leaves plenty of room for Eminem’s voice but does little to help him. There’s a lack of suppleness in the backing music, and that’s a problem if your approach to rhyming is “and and and.” His current take on “themes” doesn’t help, either. “Ass Like That” is one of many icky songs, a train wreck of failed sketch comedy. Eminem raps in what may be a South Asian accent, or possibly an imitation of Triumph the Insult Comic Dog. There is a chance that he is simply making fun of non-Americans who get pulled over by the police. Before any of this becomes clear, or funny, we get an illogical chorus about impressive butts and a sitar phrase tied to a fifth-grade discussion of erections. The whole album is filled with this kind of thing. Listening to it is like being hit in the arm by someone’s little brother forty-five times in a row.

“My First Single,” one of the few vigorous songs on the record, falls on Eminem’s plastic sword. “This was supposed to be my first single but I just fucked that up, so,” goes the chorus, interrupted every few seconds by very convincing bathroom noises. The verses are a patchwork of strategies that he’s worn down to the nub—disguising homoeroticism as homophobia, savaging people who don’t like his lyrics, spitting out a list of pop-culture names like Paris Hilton and Britney Spears. By the end of the song, Eminem doesn’t seem to remember what he’s rapping about.

When he can’t find anyone new to attack, Eminem reaches for his two longest-running characters: an evil, drug-taking mother named Debbie and a crazy, hostile ex-wife named Kim. On prior records, he raped and killed his mother, killed his ex-wife twice, and served both of them enough abuse that fans can sing along with Eminem’s hatred. We get more this time: “Crazy in Love” extends Eminem’s bilious assault on both mother and wife, “Puke” focusses solely on Kim, and “Evil Deeds” furthers his humiliation of Debbie Mathers, his mother, by apologizing to his absent birth father, who, on previous records, was just another enemy. Like many of Eminem’s other targets, Debbie and Kim Mathers are in no position to fight back. They are helpless people with the same names as the characters Eminem has created, vessels for his permanent anger. They don’t put out records, don’t appear on MTV, don’t get interviewed. Not much of a fight.

So we have to ask: Slim? Marshall? Eminem? You’re thirty-two, and you talk in interviews about how hard it is for your daughter to see her mother in jail. And, thanks to “8 Mile,” we know about the trailer home and the rough early life. Wasn’t Debbie Mathers going through all that, too? You’ve killed and rekilled the women around you—hasn’t catharsis kicked in? Couldn’t someone with your talent for role-playing maybe change things up and write a song from their perspective?

One song makes “Encore” and Eminem hard to dismiss. Less than two weeks before the election, Eminem released the video to “Mosh,” another track from the album. Most people heard it first by seeing the animated video on the Internet. Hours after it was released, I was receiving e-mails and calls from people asking if I’d seen it. More than one person was on the verge of tears.

The same guy who made his “pee pee go da doing doing doing” produced a sombre but furious jeremiad against President Bush. At last: Eminem was behaving like the badass he’d always claimed to be, taking on somebody his own size in plain view of the Patriot Act. Whatever lip service other musicians have paid to the idea of protest this year, nobody else this popular released a song this angry. A long, gloomy modal melody arcs over the rhymes. The beats are so slow that they tense up rather than deflating. The cartoon people in the video—soldiers, wives left at home—march behind Eminem and his rage: “Strap him with an AK-47 / Let him go fight his own war let him impress daddy that way / No more blood for oil, we got our own battles to fight on our own soil / No more psychological warfare to trick us to thinking that we ain’t loyal.” The video ended with a supertitle on a black screen: “Vote November 2nd.”

The truth is, Eminem could not survive on righteous fare like “Mosh.” It’s not his style, and after a few tracks like this he’d probably lose a chunk of his audience. Eminem’s mode is the childishly profane, the comically exaggerated—he’s more Benny Hill than Lenny Bruce. But on “Encore” he sounds like neither; he’s buried too deep inside his own problems to see the audience. It’s time for Eminem to look for subjects outside his head. And leave the family alone. ♦