See the "Full Faith and Credit" clause. Federal legislation in 1790 mandated that the public acts of the states be recognized by the other states. They did not limit what those actions were.
This is putting state laws above constitutional laws which contradicts the supremacy clause. Every state that seceded put state laws above constitutional ones. In fact, many said as much.
You are still confused about the Supremacy clause. State constitutions and state laws are supreme where the US Constitution has not been delegated authority.
It may seem very extraordinary, that a people jealous of their liberty, and not insensible of the allurements of power, should have entrusted the federal government with such extensive authority as this article conveys: controlling not only the acts of their ordinary legislatures, but their very constitutions, also. The most satisfactory answer seems to be, that the powers entrusted to the federal government being all positive, enumerated, defined, and limited to particular objects; and those objects such as relate more immediately to the intercourse with foreign nations, or the relation in respect to war or peace, in which we may stand with them; there can, in these respects, be little room for collision, or interference between the states, whose jurisdiction may be regarded as confided to their own domestic concerns, and the United States, who have no right to interfere, or exercise a power in any case not delegated to them, or absolutely necessary to the execution of some delegated power.
St. George Tucker, Blackstone's Commentaries, 1803, Vol 1, pp. 369-70.