I think that myths are important in understanding the gods. I personally view them like I would view a legend -- the stories in their roots are based on real events, but as stories get retold, they get exaggerated. The stories of the gods in some cases happened on Earth, but most of the time they happened in the Spirit World. Ishtar did decend to the underworld -- but it happened in the Spirit World, not here. On the other hand, the Illiad and the Aenead happened here on earth, perhaps the story as it is now is exaggerated, but it happened.