Excellent observation! Not only schools failed to educate, but MSM has chosen to ignore. The whole model of the 'United States' in the public consensus today is that it is one huge unified autocracy.
IMHO, this situation may be an unintended side effect of the American Civil War. Lincoln intended to 'preserve the Union', but the effect seems to be to have diminished state's rights.
IMHO, the fault partially lies in the term 'civil war'. Look the term up in a dictionary; it is defined as two or more factions fighting to gain control of a sovereign state'. BUT, the South did not wish to impose power (slavery) upon the North - they wanted to dis-unite from the Union and form a new sovereign aggregate of states. That is NOT a civil war; it has more properly been called by some ''the war between the states.''
From that time onward the idea of the United States being a Union between sovereign states has diminished currently into oblivion. A few years ago on FR, when I proposed secession as a possible alternative to civil war, one poster labeled that treason, which indicates just how much our understanding of our founding contract is misunderstood.
2 Documents you need to refer to...
Articles of Confederation - Predated the Constitution and were the original agreements that bound the colonies together
However...
They proved to be inadequate and so the Constitution was developed and ratified, it replaced the AoC and was ratified in I believe March of 1789
Elements of both were in there and it was till somewhat malleable in execution especially when it came to States Rights versus Federal ones.
It all settled down to the current state of being where States can have their own laws and Federal ones in general deal with the overall populace of the United States in matters of specific natures, and states can still create laws within their borders that deal with their own populace separate and aside from the overall one
The issue you mention goes back to the 2 core documents and the overall nature of the Union which by that time included other new states that were not part of the original pact and as such created issues with the new broader position of the United States under the Constitution
Secession break down in the midst of all of this and is probably in part why the California state slit into 3 was nixed by the Supreme Court here. Secession in general is not an option that can and will be tolerated as you then remove yourselves into a configuration of states at odds with the Constitution itself and it’s authority over all the states at large