There is no such thing as “states rights”, the proper term to use is state powers.
States have no rights but only powers delegated to them.
Amendment X:
“The powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people.”
You cannot delegate individual rights as they are unalienable, as stated in the Declaration of Independence.
What governments have are powers. Observes Ayn Rand:
“[George Wallace] is not a defender of individual rights, but merely of states’ rights—which is far, far from being the same thing. When he denounces ‘Big Government,’ it is not the unlimited, arbitrary power of the state that he is denouncing, but merely its centralization—and he seeks to place the same unlimited, arbitrary power in the hands of many little governments. The break-up of a big gang into a number of warring small gangs is not a return to a constitutional system nor to individual rights nor to law and order.” [“The Presidential Candidates 1968,” The Objectivist, June 1968, 5]
I do agree, in principle, to limit the federal government to its explicitly stated powers enumerated in the U.S. constitution, as the federal government has far overreached its powers.
Decentralization (or centralization) in government is only good to the extent that it enables the protection of individual rights. What the right mix is of central vs decentralization in any given context is a practical matter.
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What of the American civil war?
There’s no such thing as the right to fight a war for slavery, which is the “custom” that the South was fighting for in the American Civil War. Law is not an end in itself.
Objectively law does not exist in a vacuum, but has a purpose. Under Americanism, that purpose is stated in the Declaration of Independence: the protection of individual rights. So any state in the Union cannot legally fight a war that undermines the basis of law itself. Any republic which legally protects slavery is illegitimate to that extent. The civil war was the way this defect was remedied.
Prior to the 13th amendment the North was working to legally limit slavery and its expansion so that the non-slave states “free states” would eventually outnumber the slave states of the South. The South saw the writing on the wall. If the North was not gradually working against slavery, the South would have stayed in the Union.