What does it mean to say that civil liberties have become a national rather than a state concern?

As a young country, the United States was very concerned with distancing itself from its tyrannical former government, England. The Founding Fathers were especially concerned with limiting the power of a large federal government. After all, they had just thrown off a large federal government! To them, state governments (which were a radical new idea) represented the culmination of true civil liberties. 

Consider this quote from James Madison in the Federalist Paper No. 45: 

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As a young country, the United States was very concerned with distancing itself from its tyrannical former government, England. The Founding Fathers were especially concerned with limiting the power of a large federal government. After all, they had just thrown off a large federal government! To them, state governments (which were a radical new idea) represented the culmination of true civil liberties. 

Consider this quote from James Madison in the Federalist Paper No. 45: 

"The powers reserved to the several States will extend to all the objects which, in the ordinary course of affairs, concern the lives, liberties, and properties of the people, and the internal order, improvement, and prosperity of the State."

This was how the United States began, with state governments, rather than the national or federal government, being primarily responsible for "lives" and "liberties." 

Many things changed over the course of United States history. Those changes have shifted the balance of power, especially in the area of civil liberties. Now it is the federal government that primarily enforces civil rights laws. 

What events lead to this change? Here are just two of the many:

Jim Crow Laws and the Civil Rights Movement: With racist and violent laws being enforced in the deep south, it became clear that state governments were more susceptible to the prejudices of their citizens than the national government. Racist attitudes ran deep the the South, so racist laws were enforced. That doesn't seem to be the most consistent way to enforce civil liberties. 

War and Terrorism: Because war has such a drastic effect on civil liberties (consider the Patriot Act), and because the federal government (not the individual states) has control of the military, it only made sense that the federal government began to concern itself more and more with civil liberties.