I personally feel that Roswell was a hoax perpetrated in order to draw attention away from something else.
I have seen enough evidence to satisfy my curiosity and to tell me that there was NO crash there in 1947. The myth has been in part been secretly fueled by the Air Force with one hand, and denied by the other.
That "nurse" that pops up in some of the stories, wasn't even assigned to Roswell Army Air Field at the time of the alleged incident. The particular person cited to have been there was cited to have been emotionally and psychologically unstable and prone to hysterics.
But is that part of the hoax, or the cover up?