Activist movements need to be a bit smarter. They need to stay focused on their goals and also be aware that they will get trolled hard. I am currently invested in a student movement that, the day after their march, gained a lot of condescending criticism. And you know what, as much as I believe in it... much of the criticism was deserved. Many students can feel passionately about something without necessarily having educated themselves on the finer points of argumentation or debate. While not an indictment of their goals, in itself... they can look like fools.
Anyway... A cursory check of the members of the "White Student Union" group would surely have shown that none of the members actually go the the college campus, right? Furthermore, since things online can be faked with relative ease, it is hardly anything to get angry over. (Wait for a white power march... or racist terrorism, then get angry).