the struggle is not new -- it's been going on in social circles since charles darwin published his On the Origin of Species in 1859, and in u.s. courts since the scopes trial in tennessee in 1926 (a trial portrayed in the film "Inherit the Wind"). creationism, and its more recent manifestation intelligent design, have taken their lumps in a series of closely-watched court cases over the years, particularly with regard to whether they should be taught as science in public schools.
the linchpin to the debate is this -- to be considered science, any system of ideas or beliefs must be testable within the scientific method -- which establishes a consistent and rigorous series of steps for positing and testing any explanation of natural phenomena. one of the fundamental premises in this process is that any hypothesis must be falsifiable, that is, stated in such a manner that, now or in the future, it is possible to put forth evidence to refute the hypothesis. anything less, anything that calls for a leap of faith, IS NOT SCIENCE. it might be religion, it might be tradition, it might be superstition, but it is not science. in science, in contrast to religion, ideas may always be proven untrue, but they are never regarded as proven true.
this seems paradoxical at first, but when you give it some thought, it makes perfect sense. think about all the perceptions or beliefs (often perpetuated by religiion) which, over the centuries, have been disproven -- that the earth is flat, that the earth is at the center of the solar system, that the universe is only 6000 years old, et al. science must be falsifiable to leave room for new understanding as it emerges.
this essential condition of scientific inquiry is what makes it impossible for creationism or intelligent design to be legally taught in public schools without violating the constitutional guarantee of separation of church and state. the law does not make belief in creationsim or intelligent design illegal -- it merely states that their proper place is in a religious setting, not in the public schools.
a NOVA special on PBS, "Judgment Day: Intelligent Design on Trial", very eloquently and clearly presents the cases made by both sides -- i was deeply impressed by the show's low key, and the respect and fairness with which it treated both sides of the debate during the court case in dover, delaware, after the school board tried to force science teachers to introduce intelligent design into their classes. the special is available on DVD, rentable through Netflix, and i highly recommend it to everyone, young people and adults alike.
a footnote: one of the refrains recited ad nauseam by opponents of evolution is that it is "only a theory". this is deliberate and shameful deception. many words hold multiple meanings in the english language, and theory is one. in common usage, it means a speculation, an idea or explanation that has not been tested or accepted. within the lexicon of science, the word theory holds a more specific and restrictive meaning, i.e., a hypothesis that has been repeatedly tested, validated, and stood the test of time until it is widely accepted as a true explanation for observed events. note that, true to the tenets of science, a theory remains falsifiable. darwin's original idea (evolution through natural selection) has undergone modification in the 150 years since he first proposed it, since he did not have access to an understanding of the mechanism by which species evolve, i.e. genetics. it was only after darwin died that gregor mendel, and later watson and crick, clarified the how of evolution. these modifications notwithstanding, darwin's brilliant grasp of the fundamental process has indeed stood the test of time, and is accepted as true by thoughtful scientists and lay people around the world, people of all religions or none at all.