Generally I tend to support the idea of folks being in control of their own destiny, but I can see why a larger government would not want to allow it. The smaller local government only needs to worry about what is best for itself, while the larger government must think about the nation as a whole.
Looking at California, or New York. If the two decided to separate from the United States, what would be the economic impact to the remaining states in the nation? I’m no economist, but it doesn’t seem good. I imagine this is also true for regions or areas that have strong natural advantages as well. Such as ports which offer military and trade benefits.
I can see both sides. I can feel for folks that want to separate, but also can see why they would not be allowed.