There's a common phrase "the blind leading the blind", to describe a hopeless situation. Now there's also a common stereotype that blondes are dumb. So basically he's just playing with the phrase a little.
Bono on If God Will Send His Angels(Q Magazine, March 1997) :
"It's this guy beating up his girlfriend about her searching for answers and just telling her to look around. It's like science fiction gospel. Edge is calling it country hip-hop."
Taking that into consideration, to me the song has always been the sort of "ranting" of a guy berating his girlfriend for having faith and beliefs, because he's lost his faith. In that interpretation, the line in question is a play on words accusing the religious leaders she's following after as "the blind leading the blonde" with the girlfriend being the blonde.
Edge is funny 
Originally posted by Remythere's also a common stereotype that blondes are dumb
Originally posted by zooTV4all[..]
...which is one of the most stupid sterotypes there is.
Originally posted by Remy[..]
Probably said by a blonde guy?
Originally posted by zooTV4all[..]
...which is one of the most stupid sterotypes there is.
Originally posted by theedge123Haha country hip hop
Originally posted by sadb7788[..]Edge is a good friend
Originally posted by LikeASong[..]Really? Do you know him?