It isn't unusual for the press to confuse the Army with the Marines. As you point out, there's a bit of a problem with the aforementioned article. Here's why: From the article: Matt Stone and Trey Parker, the creators of South Park, were given a signed photo of Saddam Hussein * by US marines * after the former Iraqi leader was shown their movie in prison. But, then, further down: Stone, 37, said both he and Parker, 39, were most proud of the signed Saddam photo, given to them * by the US Army's 4th Infantry Division *. And then Matt Stone includes the following: "I have it on pretty good information from the * marines * on detail in Iraq that they showed Saddam the movie." And, to those of you who think that watching South Park: Bigger Longer & Uncut back to back is a form of torture, jfc, man up.

In this instance, it is irrational. There isn't any evidence to support the claims made by anti-vaccination groups and/or the parents of autistic children. This is why they are often referred to as "true believers".