Is it okay to blame an entire class of persons for what a few have done? The myth of illegal immigrants spiking the crime rate helped kill immigration reform in 2007. And it helped pass Senate Bill 1070, Arizona's ethnic-cleaning legislation.
It might work again. It's one of the oldest tools of propaganda and control, used to inspire pogroms, whip up hatred, play on ancient fears.
The "logic" involved is that of a child's. All of the undocumented bear the sins of one or a handful. The fear has often been more general, a fear of foreigners, a fear of anything not like oneself.
What about this murderess Jodi Arias, proof positive that all who hail from Salinas, California, are maniacs? If she had just stayed put, Travis Alexander still would be alive.
Or John Walker Lindh, the "American Taliban." Baptized a Catholic, I hear. Well, that explains everything, doesn't it?
All of your great serial killers -- for the most part -- all white dudes. Ted Bundy, John Wayne Gacy, BTK.
Those ofays have a monopoly on crazy; e.g., Jim Jones, David Koresh, Marshall Applewhite, and so on. Mass murder? With Joseph Stalin and that swastika guy on the History Channel in the Caucasian camp, other races and ethnicities don't stand a freaking chance.
White people, they're evil.