Several petitions are under way for various states to secede from the Union.
Be careful what you ask for.
What the proponents of secession ignore is that the United States is and has always been a country with a mobile population. Not only was the United States started by people who moved from other countries or their descendants, but these people kept moving west, often overrunning people already there. In the Twentieth Century people moved in almost every direction. Small town people went to the big city. People moved from one city to another to seek different opportunities. Corporations moved people from state to state for many reasons. I myself have lived in three states and my wife in six.
If a state were to secede, what would they do about "immigration"? Would business people from other states need a passport to do business in the independent state? Would tourists need a passport? If no passport were required, what would the independent state do about "illegal immigration".
What about people in the seceded state? Would they need passports to work or vacation in other states?
What about all the wars that the United States has been involved in? Would seceded states continue these wars? Often the states with secessionist movements have a significant portion of their populations who are bellicose. If the seceded states were involved in their own foreign wars, would they drag the United States into their wars?
Speaking of war, wasn't it a Republican who led a war against states seceding from the union? Isn't it ironic that some of the major proponents of secession call themselves Republicans? Did Lincoln "die in vain"?