How has federalism changed over the years?

Over the course of the American history, federalism has been evolving. During different times, the balance of power and boundaries between the state governments and the national government have changed significantly in the twentieth and twenty first century.

For the first 150 years of independence, the American republic practiced what would be referred as dual federalism, also known as layer cake federalism. During this period the American republic experienced the leadership of both the state and the national government. Each level of government had its own sphere of authority. The national government for example, dealt with national defense, foreign policy and fostering commerce whereas, the state government dealt with local matters, economic regulations and criminal law.

 After the southerners were defeated during the American civil war (1861-1865), they seceded from the federal union. This lead to fourteenth amendment by Abraham Lincoln and many of the northern states. In the amendments, states powers were limited and there was the protection of basic human rights in the constitution. 

 Globalization and industrial revolution (1865-1945) caused the national government assume a larger role. This was because the federal government was much better equipped than the states to deal with this change. Globalization led to America trading heavily abroad due to its vast economy and extensive trading networks.

Presently the federal system has become intertwined (marble cake). There is a school of thought that thinks that more power should be devolved to the states which are better equipped to deal with local issues.

References

http://www.law.cornell.edu/wex/federalism

http://www.sparknotes.com/us-government-and-politics/american-government/federalism/section2.rhtml