The image used to be here -
I found the image on a Myspace page.
The image also happened to be on the site www.americansarebrainwashed.com.
I don't think that any Americans actually are "brainwashed" -- whereas that site name suggests that all Americans are brainwashed. There are Americans who resist or stray from the status quo, and the word "brainwashed" is over-the-top enough to be ridiculous.