You are a discerning music fan with money to burn and nowhere to be the evening of June 14.On one side of town, you have one of the biggest rock bands of all time, one of the greatest live acts the world has ever seen, delivering a 30th anniversary performance of their watershed work, an iconic album that spawned some of alternative music's most beloved songs, took them to the cover of Time and cemented their legacy as crucial figures in music history.On this side of town, you have U2.On the other side of town, you have an incandescent new talent, a uniquely creative and inspirational figure who, at 24, is not only hitting his prime, not only the Grammys' reigning best new artist, but a guy who feels like he might actually be one of those rare voice-of-a-generation types — the type of act, you could argue, U2 used to be.On this side of town, you have Chance the Rapper.One night. Two artists: U2 at Raymond James Stadium, Chance the Rapper at Amalie Arena. One is set 30 years in the past. The other looks to the present and future.Which do you, the discerning music fan, want to see?• • •Fans have a complicated relationship with nostalgia. We'll bemoan the lack of new ideas in Hollywood, yet shell out millions on Kickstarter for revivals of Veronica Mars or Mystery Science Theater 3000. We'll rip on artists who keep exploring the same old tropes and themes, then lay on the backlash if they dare step outside their comfort zone.And when it comes to our favorite bands, we want them to stay forever relevant. But we also want them to play the hits.U2 has never had a problem playing the hits. If you've seen the band live at any point in the past 30 years, there's a very good chance you've already heard tracks 1, 2, 3 and 4 off The Joshua Tree — Where the Streets Have No Name, I Still Haven't Found What I'm Looking For, With or Without You and Bullet the Blue Sky. When they perform the album in full during their Joshua Tree anniversary tour stop in Tampa on June 14, a lot of it will feel just like any other U2 concert — which is to say, passionate, spectacular and larger than life, perhaps even transcendent.But U2 also has never been, well, stuck in a moment it couldn't get out of. Every step of the group's career, from unqualified highs like The Joshua Tree and Achtung Baby to divisive gambits like Pop and Songs of Innocence, marked an attempt to push the band forward in some way — sonically, emotionally, artistically, technologically. They have always aimed higher, dreamed bigger, reached deeper than their peers — and for that they have been mocked, but also embraced and adored in ways few artists will ever know.And that's why the idea of an anniversary tour — even one for an album as indispensable as The Joshua Tree — felt like such a retrograde move. When the tour was announced in January, the indie music news site Pitchfork tweeted without mercy:Does U2's Joshua Tree tour mean they're ready to accept their status as a legacy band? Are U2 finally putting their work behind glass? Maybe U2's Joshua Tree tour will remind fans that they used to actually be an exciting band.A few days after the tour started, Tony McGuinness of the British electronic group Above and Beyond found himself surfing through photos and videos. It all looked well produced and executed, he said, but something about it didn't ring true."I can't imagine that sort of thing happening years ago," said McGuinness, 48, a former major-label marketing executive. "I think the whole idea of acknowledging that there is this thing you've done that exists in millions of people's front rooms, which is that album and that sleeve, and what it meant to people, and coming back and saying, 'Okay, we'll play that for you' — it's a very un-rock 'n' roll thing to do. It's like they are allowing themselves to play a role which has been defined for them by history and by their fans, for the most part. This is not a thing that I'm sure is coming out of the postpunk Bono brain. I'm sure if you'd asked him back then if he could ever envision a time in which they do this, he'd be like, 'Absolutely not.' "There's a tension that runs between playing the old stuff and the new, and it cuts to the heart of the divide between artist and fan. Most artists would rather look ahead, playing the music that moves them at that moment. But the hits are what keep selling tickets.Third Eye Blind is crisscrossing the country this summer on a 20-year anniversary tour of their self-titled debut album. Singer Stephan Jenkins, who saw U2 growing up in San Francisco and opened for them on the PopMart tour in 1997, said he's proud to have the opportunity to relive his band's biggest commercial success: "It's quite a thing to have an album that goes for 20 years," he said. But it won't stop him from playing newer songs, too."I don't give a damn about nostalgia," Jenkins said. "I want it to feel alive and vital and interactive with what your take on the zeitgeist of sound is right now. That's kind of where I'm at."But you know, if I went and saw the Rolling Stones, I'd love for them to play Tumbling Dice," he continued. "When we play Jumper, and the whole place really lifts up, I'm right there. I love it. I love being part of it. I just feel gratitude and joy in it. The people into it are keeping your music alive. And I think that's incredible."• • •If they weren't playing in Tampa on the same night, U2 and Chance the Rapper would probably love to meet up. Both acts' uplifting music overflows with themes of spirituality and social empowerment. U2 loves conscious hip-hop; they recently featured on Kendrick Lamar's song XXX. Chance leads a sizzling live band steeped in jazz and soul. They're co-headlining this weekend's Bonnaroo music festival in Tennessee. They're probably fans of one another.So why does U2's Joshua Tree tour feel so anathematic to young fans entranced by Chance the Rapper — or Kendrick Lamar, for that matter, or Lorde or the Weeknd or Halsey or any other artist under 30?Music never sounds better than it does when you're young. If you were 18 when The Joshua Tree came out in 1987, you were probably locked in for life. If you were 18 when Chance dropped Acid Rap in 2013, you were probably locked in for life. And while that passion might not fade, the years will roll on, and those seminal works will drift further into the rearview. No matter how revolutionary an artist may seem, they, too, will inevitably hear cries to play the old stuff.Bryce Avary, 34, caught U2's Joshua Tree tour in Dallas. He knows a guy who works for the band, went backstage and talked with the crew, even snagged an Edge guitar pick. He also leads the pop-punk act the Rocket Summer, which is about to embark on its own anniversary tour, celebrating the 10-year mark of the album Do You Feel.Ten years. The lifespan of the iPhone. Nostalgia happens that quickly."Of course, it's not even in the same galaxy as Joshua Tree," Avary said of Do You Feel. But he recognizes there's a community of fans who were 18 in 2007, 28 today, who connect deeply with his album, too."There's kind of this youthful, optimistic magic in the songs," he said. "Having to revisit it, it's making me realize, Wow, there is something special in this album. I understand why people connected to it in that era."U2 realizes this, too. Their last album, 2014's Songs of Innocence — the one people howled about receiving for free on iTunes — was rooted deep in their past, its lyrics referencing the band's early days in Dublin, and all the unrest and upheaval and inspiration therein. From that point, the Joshua Tree tour feels like a natural progression, revisiting a later but just-as-crucial point in the band's existence.In looking back, the band is trying to push itself toward something new. The songs they're playing are 30 years old, but in some cases haven't been performed live in decades (Exit, Trip Through Your Wires) or at all (Red Hill Mining Town). They're even closing with an all-new song, The Little Things That Give You Away — a window into their next album, which could come as soon as this year.Oh, I'm not a ghost now, Bono sings. I can see you. You need to see me.You can see U2 on June 14, or you can see Chance the Rapper. Both are worthy choices. But neither is a ghost. Both are fully present in 2017, alive and of our time, no matter how fans from other generations view them. The memories they make in Tampa might last 30 years.Contact Jay Cridlin at [email protected] or (727) 893-8336. Follow @JayCridlin.