Lady Gaga never saw it coming. After a relentless, mammoth, publicity extravaganza for her new album, ArtPop, she was upstaged by a comet seeming to swoop in out of nowhere — the release of Eminem’s The Marshall Mathers LP 2. Eminem’s sales boomed big, while Gaga’s embarrassingly fizzled, leading to quick deep discounts to keep ArtPop on the charts.

Eminem, now 41, did few interviews and personal appearances for this formidable double album. As with Adele sweeping the Grammys two years ago, his instant commercial triumph demonstrates the readiness of a discerning world public to respond to power and passion of voice rather than to manipulative gimmicks or exhibitionistic stunts.

The greatest irony is that Gaga, product of an affluent Manhattan home and a private-school