The debate over whether the Scottish region of Great Britain should secede from the UK extends beyond whatever provincial interests unite and divide the state’s regions; it "is also part of a larger question that extends well beyond Britain, to Texas and Colorado, for example, and elsewhere: What are the benefits and drawbacks of larger, politically diverse countries, compared with smaller, more homogeneous ones?" Yet is Britain a large, heterogeneous country even as it is a state in the European Union? Texas is much larger, and yet it too is a state in a union of relatively homogeneous states.
Moreover, rather than treating large, diverse countries on one side of a spectrum and small, relatively homogeneous countries on the other, the two political types can be viewed as qualitatively different—meaning that they are on two different political levels. Generally speaking, an empire is a very large, diverse country or union that consists of relatively homogeneous “kingdom-level” (i.e., smaller) countries or states. Indeed, modern federalism allows for both the empires and their respective states to have elements of “countryhood” even as two distinct levels are involved: the federal and that of the consisting states.
Because an empire consists of a large number of such subunits, neither the UK nor Canada can be said to be empires, whereas the E.U. and U.S. can. So comparing Britain to Texas and Colorado in terms of secession should be done carefully; done wrongly, a category mistake may be involved. Such a mistake treats a state in one empire as being on the same level as an entire empire elsewhere, or one empire like a state in one’s own empire.
According to The New York Times, UK spending in the Scotland region of the state benefits from wealthy London taxpayers. The article goes on to the troubled waters of comparisons. "There is an echo of this debate in the United States, even if the political sides tend to be switched. In Colorado, some conservative rural residents have raised the prospect of breaking off from the rest of [Colorado], which is both more liberal and more affluent. More broadly, many conservative states in the United States, like South Carolina and North Dakota, receive many more tax dollars from Washington than they send there." It is the “more broadly” pivot that is problematic, for the move from intra-Colorado, or intra-Britain dynamics to interstate dynamics in either the E.U. or U.S. involves taking on additional (interstate-only) dynamics.
Specifically, it is one thing for a region of a state to split off, and quite another for a semi-sovereign member-state of a union to secede. For one thing, international principles apply only to the union, and they complicate any intended comparison with a state. Furthermore, it is one thing for a region in a state to justify leaving a state with a low or moderate amount of regional diversity relative to that of a union of many formerly-independent states, and quite another for one of those states to justify leaving an inherently diverse (i.e., by territory) union.
Scotland breaking off from Britain, I contend, is rightly commensurate to Eastern Colorado breaking off form Colorado and Southern Illinois, which is called Egypt, breaking off from the Chicago-dominated Illinois. Scotland is not like South Carolina seceding from the U.S. in 1861; rather, the UK is like South Carolina in deciding whether or not to secede from the European Union. Just as the Federalists and Anti-federalists debated in the early U.S. whether the states or the federal level should have the balance of power, so too Euro-federalists and Euro-Skeptics have debated the same question in the first fifty years of the EC/EEC/E.U. Attempting to liken the arguments on the Scottish question to those being made in Britain on whether the state should secede from the E.U. is likely to be an exercise in futility; the vast qualitative difference between the two political levels cannot but elude such an exercise.
 Katrin Bennhold, "How Scottish Independence Relates to Larger Tax Fights," The New York Times, August 21, 2014.