To answer the original question:
1. Culture, socialization, and stability of group attachments: If there is one thing we know, group attachments are incredibly stable over time, so it is very difficult to change these once they take root, and Americans have a long history of religious belief. For instance, if you look at the data, younger people are about 10 percent less likely than other age categories to be religious because they have grown up in an environment that is less enamored with religion.
2. Question wording: Other gallup polls actually show that a majority of people believe evolution is true or probably true. Giving people the options presented in the original survey unnecessarily primes religious themes. Just asking people whether they believe in evolution or belief in creationism is a better method. I also think we need a lot more knowledge about what people think of when they are asked about evolution and creationism. For instance, whether they view them as being incompatible.
http://www.gallup.com/poll/21814/evolution-creationism-intelligent-design.aspx
3. Whose fault? No one in particular.
