How do you differentiate between a "reaction" and a natural consequence? Maybe as religion / superstition diminished, that left an identity vacuum which was filled by nationalism?
I don't. The main work of the Enlightenment was to end religious wars, and I don't think that should not have been attempted because religious wars would be replaced by national wars. We have to keep working through all the crises that ensue. Blaming the Enlightenment for all the dominoes that fell over removes responsibility for other actors and currents, and makes the Enlightenment a scapegoat.