Yes, but it still happens within the constitution. That is where it always ends in practice.
Because the Constitution is the supreme law of the land.
*
What the local government does, does that fall within the constitution?
There are no state rights themselves, they are within the constitution.
True enough -- but the Tenth Amendment gives the states full authority regarding any matter that the Constitution
doesn't say anything about -- age of consent for sex/marriage, for example, varies from state to state.
But because the Supreme Court gets to decide the Constitutionality of the actions of the other two branches
**, the Constitution says whatever the Supreme Court
says it says.
And since the American justice system is a Common Law system, we have "vertical stare decisis": judicial decisions from higher courts are binding to the courts beneath it...and when the Supreme Court makes a decision, well,
every court is beneath it, isn't it?
The matter is considered settled, because the only court that can change the Supreme Court's decision is... the Supreme Court itself, in a later decision
***.
*it says so. (convenient, isn't it?)
**they said so in Marbury v Madison (1803) (convenient, isn't it?)
***VERY convenient, isn't it?