There's a really good On the Media about this very topic (which I can't link to, because the fascists in my IT dept have, for some unknown reason, blocked OTM's website here). They point out that 50,000 is the number of abducted children that everyone from the media to the FBI used to throw around in the 80s and 90s. When some thought to actually measure the number it turns out that the average number of children abducted by strangers annually in the US is about 200. Or, 250x lower than what was claimed. Another tidbit they throw out that I loved: the media also used to say that Satanic cults abduct or kill up to 50,000 people per year (same number, un-coincidentally). The actual number there is about 0, or a factor of infinity lower. What a joke the news is; they are to blame for this mentality (bot solely, but in large part).