Eminem, Hampden Park, Glasgow, June 24

Just when did Eminem get this big? With a condescending nod to Robbie Williams’s Murrayfield shows this weekend, this was the musical event of the Scottish summer, a state visit from pop royalty. The surly superstar acknowledged as much himself with an entourage of burly security that followed him everywhere in the days before the show, and with the cute stunt he pulled from his Glasgow hotel balcony, brandishing a doll in a satirical Michael Jackson reference.

It’s worth making the comparison with the dethroned king of pop. A generation ago it was Jackson’s innocent disco that had the world’s youth in thrall. In a grubbier century, Marshall Mathers III has tightened his grip on every lucrative constituency with a smart, profane brattishness that strikes a chord across the age groups, eliciting both the adoration of 12-year-old girls and the critical enthusiasm of the greying pop theorists.

This week’s Eminem is a performer just crossing over from counterculture hero to mass-market ubiquity. Last year’s biopic, Eight Mile, tried to reposition him as an all-American hero, a trailer-trash kid embracing the values of persistence and single-minded ambition. It was A Star is Born, punctuated with the “mother” word, slotting Eminem neatly in the file marked “American showbiz stories”.

He got this far by identifying and personifying a universal teen sullenness, by embracing his folk-devil status, delighting in and amplifying a perceived outsider status that in truth amounts to no more than his penchant for regular reference to drugs, sex and violence, which, let’s face it, have really been the lexicon of popular music for half a century. The dumb American senators who think he is a social menace are all given a few seconds to hang themselves in the live show’s opening sequence video.

The stage set, with the big wheel and the carnival pyrotechnics, underlines one of Eminem’s multiple images, as the huckster with the hard sell. His instinctive sense of showmanship was enough to lift him out of the preaching-to-the-converted genre into the realms of mass adoration.

The problem is, that when he staggers to the stagefront and crouches to deliver his opening salvo, what comes out sounds like he is gargling into a bucket. Eminem’s rhymes might be cuter and acuter than any of his rap rivals, but you’d never know it from seeing this show, where every syllable disappears into a muddy cloud above Mount Florida, bludgeoned by acoustics designed for channelling the Hampden roar rather than focusing vocal delivery.

Like any aggressive music, rap is neutered in a stadium. The bite of the beats and the words has to be witnessed ringside, you need to see the anger of the expressions, feel the sweat flying. The faked-up rap “battle” scenes in Eight Mile had far more thrilling visceral atmosphere than was ever going to be achieved here. That didn’t stop thousands of arms punching the air in a sinister synchronicity, or a suspiciously sweet singalong for the girlie chorus of the fans’ anthem Stan. The message doesn’t seem to matter, because this is all about the messenger.

The sarcastic bile of White America might suggest that Eminem has developed a political sensibility, but that would be misleading. His recordings are among the most self-obsessed of any artist, tracing the story of the real Marshall Mathers, the cartoonish Slim Shady, the ringmaster of The Eminem Show. The subject matter might leap around the US, offer a few scattergun asides at the state of his nation, but his views on his country are always secondary to his delight at the reaction he provokes there. He has taken three multi-million selling albums to delineate his own multiple personalities, which must be the realisation of a real American dream. Perhaps that’s the appeal of the generational message, not one of community, but of the possibilities of marketing your personal hang-ups and prejudices, of success as therapy. No wonder he’s so successful, in the age of angry assertion of the individual.

At Hampden the show wasn’t about the music, the wit, or the lyrical genius Eminem can show on records; it was a casual assertion of his peerless grip on western youth. Right about now, Eminem is still smart enough, aggressive enough, refusenik enough to make us believe he is the one doing the selling. It’s a close thing though, and the depressing suspicion is that, just a few more hot dogs, a few more T-shirts, a few more stadium shows down the line, he will teeter over into being another rebel rendered into commodity. About then, Eminem will very rapidly stop being interesting.

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