Yes, but by the time they hit global domination levels with The Joshua Tree they were far too established (a mixture of the success of the single Pride. the release of the Live at Red Rocks video and their quite astonishing appearance at
Live Aid). I actually remember the day that The Joshua Tree was released, seeing the queues outside HMV. It was a frenzy of almost Beatlemania-like proportions. Certainly I've never seen any other band grow to that size in my lifetime. People talk about Coldplay being massive should've been around to witness U2s rise. That video for
'Where the Streets Have no Name' is one of my all-time favourite promos, showing a band that imagines itself as being at a certain level of popularity, suddenly confronted with the sheer scale of its fame. Still sends shivers to the back of my neck whenever I watch it. A remarkable time for a remarkable band.
I do still think you're right about Out of Time though. I was thinking maybe The Cure's Disintegration, but no. It can't compete with Out of Time. Although, hold on, now that I think about it, Simple Minds' Once Upon a Time might arguably offer a decent challenge. But even here, I do think we're talking about a quite different reading of the word 'alternative' to the one associated with a band like REM. It's just a shame that Out of Time happened to be such a dull album.