1. The term “Chareidi” to refer to anyone observant was in vogue 100 years ago. Since then the number of labels has grown. “Dati” refers to non-Chareidi frum.
2. So who orchestrated the rise of nationalism in the 19th century and who is orchestrating its present revival?
3. Which Chareidim? There are also various sub-groups. Besides the different Chassidic groups, there is Lithuanian, which is further divided between Bnei Beraq and Yerushalayim. There is also a new group of working Chareidim. There are the olim from America and France who are more like Chardal (Chareidi Leumi) except for not having been in the IDF. As for following gedolim, I can tell you that at least in the Anglo Chareidi world Rav Kook, Rav Yisraeli and even academics such as Prof. (Emeritus) Schochatman and Dr. Vigoda (Asst. AG for Jewish law) are quoted in shiurim (I have heard this with my own ears).