There are small groups of Christians who believe that the first couple of chapters of Genesis should be interpretted literally.
Once Genesis is interpretted literally, you can calculate the age of the earth. It is on the order of 6000 years old. Thus, the Bible becomes a history book.
===
There is a small group of atheist scientists who believe that science can be used to disprove God.
They have latched onto the literal interpretation of Genesis and offer evolution as proof that there is no God. They now defend evolution as a fact rather than a theory thats full of holes. Evolution has become the central tenet of their "anti-God" religion.
===
Most of America does not interpret Genesis literally and thinks both groups are very vocal nuts.
There are several posters on this very thread who are young-earthers.
But they won't confront you. They're shy about their beliefs.