Wild horses in the United States were once protected under the 1971 Wild Free-Roaming Horses and Burros Act, which declared "wild free-roaming horses and burros [to be] living symbols of the historic and pioneer spirit of the West." The U.S. Congress passed a law in December 2004 that made it legal for the federal government to sell some wild horses to slaughterhouses, where they are processed for human consumption.
(Photograph shot on assignment for, but not published in, "Searching for Sacagawea," February 2001, National Geographic magazine)