I have another question for the thread:
There are clearly challenges facing frum students at secular universities: Philosophies contrary to Torah (I can’t believe how many supposedly frum Jews I’ve met who admire Ayn Rand), licentious lifestyles (not a new thing), etc. I have listed a number of gedolim who attended secular university and could have listed a dozen more. My question is whether there is anything that any of these gedolim have written regarding those challenges. I have seen nothing about this in the works of Rav Hirsch or Rav Soloveitchik.