Which major event sparked the first argument over national supremacy versus states' rights?

The answer is Civil War. It was battled over the subject of national supremacy versus states' rights. It established that the national government was highest or supreme, its sovereignty or dominance derived directly from the people, and therefore the states could not legally separate from the Union.

Ifound this on google”the munich conference of 1938 was prompted by d. hitler's intention to take control of part of czechoslovakia. hitler sought to unite german-speaking people in a single nation and thus turned his sights on the sudetenland, a german-speaking region of czechoslovakia.” i hope it you