They had to go there.
Joni Ernst is running for a Senate seat from the state of Iowa. And apparently she is incapable of learning from history, or she took a crash course in stochiastic terrorism.
See if you can pick out the dog whistle.
"I grew up castrating hogs on an Iowa farm. So when I get to Washington, I'll know how to cut pork," Ernst says in the commercial. At the end of the ad Ernst concludes, "Washington's full of big spenders. Let's make 'em squeal."
Now what sort of violent imagery is she trying to inspire?
A repulsive remnant of racist riots.
After he was stripped and castrated Claude Neal was forced to eat his own penis and testicles. As the angry mob of White women, men, and children applauded; he was then forced to exclaim that he liked them.  The trauma of this physical mutilation proves slight in comparison to the psychological angst inflicted on Black men daily as they watched their mothers, wives, and sisters raped and beaten while they stood powerless. The overt removal of authority within a family from a Black father to his White master, created despondency and disorder in the Black man's life. His concept of masculinity was tainted by the constant swallowing of his manhood and his inability to defy his aggressors. This original defeat ignited the spark of violence that we see today in the Black community.
In the last decade, violence in the Black community has been referred to as an epidemic, a plague, a burden on society as a whole, and a drain on the Black community itself. The brutality is often blamed on everything from the innate inferiority of African Americans to the White patriarchal politics aimed at disabling minorities.  University of Delaware Professor William Oliver states,
“Advocates of the genetic inferiority perspective argue that the high rates of social problems among Blacks is a product or expression of Black peoples' innate inferiority to Caucasians and other racial groups…(they) possess genetic traits and characteristics that predispose them to engage in problematic behavior at higher rates than Whites.” The Black Association of Sociologists then argues, “White racism is the underlying cause of the problems that blacks confront”.
However, the actual primary initiating factor is of a social origin. The particular sadistic violence bestowed upon Black men in the Postbellum South has perpetuated itself in different forms through custom, and in doing so, molded the Black male perspective of masculinity and its synonym of violence. This progression, in combination with the combating sociological theories, creates a hostile atmosphere for the modern Black man. This is not an unpredictable phenomenon; White aggression towards the Black man has been heavily contested throughout history.