Yes, the agents were trying to keep the migrants from getting out of the Rio Grande onto U.S. soil, but that is their job. What critics most dislike about what the agents actually did — the shouting, the grabbing, the maneuvering to stay in front of the migrants and try to get them to go back — was not remotely out of line, and it wouldn’t have occurred in the first place if the migrants had simply obeyed the commands to stop and go back.
Another line of criticism is that there is something inherently wrong with having agents on horseback. This is absurd. The Border Patrol has used horses since its inception in 1924 because the animals are adept at maneuvering on terrain that is difficult for motorized vehicles or for agents on foot. Besides, horses are a natural tool of crowd control and are used for this purpose across the United States, including in the bluest cities in America.
Then, there are the supposed echoes of slavery in having men on horseback harrying black people. Anyone, though, who can’t tell the difference between overseers punishing people held in bondage and agents — many of whom are minorities — enforcing the laws of the United States doesn’t deserve to be taken seriously.