Had I not known several alumni of the program, I would not have easily found out about the security studies program either. I guess since it is such a specific program with a very niche goal of preparing social science scholars to conduct applied research, they figure that those candidates who are interested in the subject matter and are a good fit will find the program. That said, I've heard from many people that they should get the word out more about it.
The program itself is closely related to the political science department—sharing many of the same faculty and cross-listing most relevant courses—but it remains an entirely unique, standalone program.