Yes, as a descendant of horse thieves and bank robbers, I am also offended!
Seriously, I can see how a noose could be used in some settings as a symbol to intimidate blacks. At a town meeting where black people are speaking in order to get better public services in a town that has a history of outright racism.
In the library at UCSD, it is not a big deal. Even if the student meant it as a refernce to the "Ghetto Party" controversy, it wasn't going to intimidate, scare or threaten anyone. It was just stupid and lame, someone's idea of a way to fight back against PC and its stupidity, not an effort to scare them.
I guess in today's world, those guys who made picante sauce in New York City are safe now. But the ones who made the ad will have to go to jail.