Since the University of Chicago left the Big Ten in 1946, Northwestern has been the only private school in the Big Ten.
Having either one or two private schools seems to be common practice for the power conferences. The SEC has Vanderbilt, the Big 12 has Baylor, the Pac-12 has USC and Stanford. The Big East has a bunch of private schools, but only one of them (Syracuse) in football. The ACC is a bit of an outlier, as four of their twelve schools are private.
Large public schools like those in the Big Ten have large enrollments and that usually translates into more money for the athletic departments. Besides Notre Dame, there aren't too many private schools that have a large, passionate fanbase among those who have never attended that or sometimes any other college. There are a lot of rabid Buckeye fans in Ohio that have never set foot on campus, but I don't think there are too many Northwestern diehards that aren't directly affiliated with the university.
Is it good for a major conference to have a single, smaller private school that has these disadvantages? I'm not trying to say that obstacles that private schools face are impossible to overcome; Northwestern has fielded a consistently decent football team for a while now, and Vanderbilt and Baylor have had some recent hoops success (to name just a few examples).
I really don't know the answer to this question. Since Northwestern has been in the Big Ten as long as I've been around, they seem like they belong to me, but they don't fit in with the profile of the other conference schools.
I'm not sure what the point of this post is, but writing it has made me think about the makeup of big-time college conferences. Which blend of private and public schools works the best in a conference?
Even if the question doesn't make sense, I'll put it in a poll anyway to see what the responses are. I am not going to include the answer "It depends on the specific schools involved", because I think everyone would pick that because it makes too much sense.