The world’s most popular rock band lives in constant contradiction. As U2 itself put it in the 1988 hit “God Part II”: “I don’t believe in riches, but you should see where I live.” The group at times proclaims Christ with power and passion, but it seems equally capable of cunning calculation. In 2004, U2 sold Apple the rights to “Vertigo,” which was subsequently played to death on iPod ads. While the hit invoked higher love (“The girl with crimson nails has Jesus ’round her neck”), it foundered from its ties to a ubiquitous gadget. Chicago Tribune reporter Mark Caro nailed it: “Its essence has become a jingle, disposable by nature.” The girl with crimson nails had buds jammed in her ears, and people stopped listening.