Many Americans are sentimental about horses and believe that American horses deserve special treatment under the law for their important roles in American culture and history. In 2006, the House of Representatives passed a bill, known as H.R. 503, to end horse slaughter for human consumption in the U.S., and the following year in 2007, the horse slaughter ban began in the U.S. In this paper, the ineffectiveness of the horse slaughter ban to protect unwanted horses in the U.S. is demonstrated. More horses have been transported to less-humane slaughterhouses in Mexico and Canada, and more horses have been abandoned, abused, and neglected in the U.S. since the horse slaughter ban began. It is important to consider how American sentiments about horses contributed to H.R. 503 to better understand the ineffectiveness of the horse slaughter ban. People who were in favor of H.R. 503 relied on animal rights arguments, which tend to be more emotional than animal welfare arguments, by appealing to American sentiments about horses. The public increasingly believes that animals have rights. If animal rights activists do not find ways to protect unwanted animals, their ideas can infringe on animal welfare.