From the Ascension of FDR to the Presidency in 1932 until the end of the Eisenhower administration in 1960, there was a consolidation of power within the Federal government in America and an increasing acceptance of this power by Americans. Also during this time the population of America became more homogeneous. The waves of immigration that had characterized American growth for the previous century slowed, replaced by the pattern of undocumented demographic influx that we see today. Large, active population shifts, within the country were completed. The movement from rural to urban areas was completed and the movement from urban to suburban areas was established as a large demographic trend.
What's been happening since 1960 has been interesting. While the Federal government has remained strong, confidence in it has slowly ebbed along with economic strength and productivity. Social class distinctions re solidified. Regional cultures have strengthened.
It seems to me that America is on the verge of some new changes. We have the strongest military in the World but can't maintain its cost. America is losing the World leadership position that it has held since the end of World War II. The Federal Government is about to lose its vast powers. It will lose these powers not because the populace takes them back but because it can no longer foot the bill for them. It cannot maintain the infrastructure, it cannot continue to fund the vast bureaucracy it has amassed, it cannot subsidize the social safety net that the populace has come to depend on. The next period of American history will be characterized by the deterioration of the military establishment and all of the other institutions that the vastly powerful American federal government has built up to sustain itself.
People think that America will be able to reform and rebuild the institutions that are necessary to continue on as a premier state. There is no unity of purpose among the people to do this and even if there was, there is no vision of what a new America would look like and how it would function. There is no immediate potential for the generation of revenue in the amounts that it would cost. Currently all anybody is interested in, is how they can salvage or patch up the individual elements of the government that benefit them the most. That is not a recipe for growth or renewal.
Big changes ahead. They will be interesting to see. If you are a big tea bagging fan of the return of governmental function to local control, you may be very happy. More control may be returned to local governments than you like.
America may become a great nation again. Probably will but it may need to be rebuilt from scratch. Getting back to scratch is going to be a very interesting chapter in our history.