The states increasingly suck on and are dependent on the federal tit for all sorts of things things they should be deciding for and providing to their own people. They have forgotten their own history as one-time independent nations or territories, and have forgotten that the federal system is a compact an agreement between the states. In neglecting their own sovereign prerogatives and ceding so much of their power to the federal entity, they have destroyed the most significant check on federal power, states rights.
Theoretically, the Civil War settled the question of secession. But the states have acted more like the War not only made it impossible for them to secede, but also made them SUBSERVIENT to the federal government, rather than the other way around. There are numerous delegates to the 1787 Constitutional Convention who never would have signed the Constitution, and many of the 13 original states which never would have ratified it, had they been able to foresee such a turn of events.