Is expulsion the appropriate punishment? I would think that if I had been caught on camera saying something like that, just being on campus would be a day to day game of who is going to just clean my clock out of nowhere.
That said, I honestly do not think they should have been expelled. Not because I even come close to agreeing with the ideology, stupidity or whatever it actually was. I don't think they should have been expelled because that is life. You are going to have sh*theads no matter what. Life is about making the choice to just move past those people. Additionally, academia is notorious for supporting "protests" of some of the most screwed up flavors... some of which I would have found downright offensive if I really got offended by the jack*ssery that other people partake in, including rallies that I have witnessed that I considered racist, sexist etc etc.
If they were protesting and actually exercising their free speech, I could agree. But they weren't exercising free speech. They were spewing hateful racist crap on a bus representing a campus fraternity. Because of that, they absolutely should be expelled from OU. They are free to appeal and free to go elsewhere for their education. I suggest the apply at Langston.