It has often been said that Achtung Baby was a train driving away from "Joshua Tree" U2. The album opens with "Zoo Station"...then breaks into "Even Better Than The Real Thing" which has an intro that undeniably sounds like a train pulling out of the station (the "zoo station)...and away from the "old U2".
In the "Electrical Storm"...we see Bono and the band on a train. So...do you think U2 might be catching at train back to Joshua Tree?? heh. Ok...seeing a little too much into it maybe...but with all the recent talk on that topic...not unreasonable, hey?