The fifty United States of America are not “united” on the basis of unconditional fealty to even a wholly legitimate federal government, to say nothing of a one or two thirds illegitimate one.
The Constitution and its Amendments were written and ratified to protect the states and, ultimately, we, the citizens, from governmental violation of our inalienable individual rights, and from whom the entirety of government derives its only legitimacy. It serves us; not we, it.
The Constitution delegates to the government certain specific, definite powers, and reserves all unenumerated powers to each State itself, leaving each the right to its own self-government in all residual affairs. Whenever the federal government—whether one branch acting alone, two together, or three in concert—exercises powers nowhere delegated to it, its acts are void—they have no authority, force, or effect.
The government created by the compact between states is not—indeed, logically, cannot be—the final, and certainly not sole, arbiter of the powers delegated to itself. That would elevate its discretion above the very Constitution from which it derives its power and legitimacy.
As with any self-enforcing contract between parties with no common judge, each party—which is to say, each State—has an equal right, indeed has an affirmative obligation owed to each of its own citizens—to affirmatively judge for itself the limits and legality of federal actions, and to decide for itself in protection of its citizens the proper mode and measure of redress for federal transgressions and usurpations.