… and the Netziv’s Zionism and his introducing secular studies in Volozhin. Admittedly Russian classes in Volozhin were only introduced under gov’t compulsion, but since the yeshiva velt felt a need to rewrite that bit of history, I think it’s still relevant. Also, RSRH found it to be embraced heartily enough that he wrote his followers an approbation for donating to the Volzhiner Yeshiva as fellow travelers down the path of TIDE!
Kelm, the mussar yeshiva, also had a HS with a full gymnasium’s curriculum for secular studies. And that was without any government involvement.
Most of the yeshivos actually encouraged informal study of other subjects — as long as the students did so in their own time. R’ Avram Elya Kaplan’s diary reports debates about topics like Freud and Marx being commonplace in the halls of Slabodka.