That's a good question. I am an atheist because I view the world as an enigma with a solution which I can find. I see things that people call miracles and I call them science. I am fascinated with mythology, Greek Mythology in particular. I know that as time progresses and we move forward, people stop relating the miracles of the world to deities and start realizing that things can be explained through logic. Centuries ago people related everything to deities. Everything had its own deity and in some cases two or three. Water had Poseidon, Neptune, Triton, and probably a few more. War had Ares, Mars, and even Athena. Even minor things like fear had gods; Demos. People would go to war over which god they were supposed to worship.
I asked myself, "If people believed these things then, why not now?" My answer came in more reading. As people became more open to new Ideas, and new ways of doing things, they found some gods to be obsolete, so they eliminated them. Unfortunately there were still things that couldn't be explained so instead of waiting around for people to pick off their gods with science one by one, they glued them together and made a single all-knowing, all-powerful Godzilla (no, not the Japanese monster...but close). Everything in the world they attributed to him. They said he had a plan and you don't so join us and have direction. Still there were problems. People had different interpretations of what "Godzilla" should do and how he should manifest himself. Some believed he was and old guy with a white robe and a beard. Others believed he was a mysterious man who created the world like a string with the past, present, and future. Some believed he wasn't a "he" at all. These different viewpoints became so different that people started fighting over them. Great wars arose because two priests disagreed over which side of His bread was buttered. The priests got control of government by saying that kings were divinely appointed, so kings and priests were on the same team. They made it heresy for anyone to go against the church. Heretics were sentenced to death unless they refuted their beliefs. People believed whatever the church said. Then the Black Plague came around and priests said it was God's punishment for sinners. Boy did things go to Hell when priests themselves became sick. The eyes of the people were opened ever so slightly and Protestantism was born. Yet another view of Godzilla. People refuted the idea that the world was flat that they had cherished so many years before and set sail for the horizon. They circled the Earth and proved wrong another of the priests "God told me so's". They colonized new lands and destroyed the people living there. They burned those who acted diferently and those who they thought acted differently.
Then finally they started to see the world under scrutiny and begin to do things for themselves. People realize that the world can be explained and they work to better explain the mysteries around them through logic. People still have their religion and attribute the good things to their god and the bad things to their counter-god, because you cant have the good without the bad.
As they explain more and more, Godzilla will lose its power and eventually fade away just like Santa Claus, the Tooth Fairy, and the Easter Bunny. I look at religion as a fairy tale. I've even heard people refer to Religion as a sinking ship and Jesus Christ is the life preserver. To them I say, "I DON'T SAIL!"