It's not just reflexively doing the opposite of what Trump wants. The core ethos of the left now is "brown good, white bad." This is a moral instinct that precedes rationality. They see a white person doing something to a brown person that the brown person doesn't like, so they take the brown person's side instinctively. Everything after that is post-hoc rationalization.
To understand this, think of witnessing a large man punching a small woman, knocking her to the floor. You instinctively see this is bad. Suppose you find out afterward that the woman picked the man's pocket, then reached for a knife when he confronted her. In this scenario, you are still likely to rationalize why the man shouldn't have hit her. Moral instincts are powerful.
Libtards have been trained their entire lives to instinctively see the white man as the bad guy in all white/brown confrontations. It's why, even when we are deporting child rapists after multiple judicial hearings, they caterwaul about due process and try to hold up flights to keep the poor little lambs "home."