A curious thing happened during and after the US election of 2008.
We've heard a native of Alaska (which became the 49th state over 170 years after USA was created) and certifiable moron proclaim that she comes from the "real America" and is running on McCain's ticket to fight for "real Americans". Her speeches to elderly sexually frustrated rural gawkers made it seem as if the urban Northeastern citizenry of United States was somehow an alien patch within the national fabric. Considering that Northeast was not a puppet state under any foreign occupation at the time, it was the equivalent of a minor Scottish politician proclaiming Scotland to be a more real UK than UK itself.
Of course it was strategically necessary for the poorly educated charlatan from country's far periphery, the wide eyed gold digger like Sarah Palin, to use terminology like this. After all, many people in the nation's interior and periphery got left behind economically by the country's slow decline of the past few decades. Politics of resentment do have an underlining psychological basis that is very real, based on real grievances, and uncomfortable if one is to dig into it from a class based perspective.
Now of course we hear rural Midwesterners and Southerners cry about wanting "their country back". Considering that the original heartland and tree trunk of United States (New England) voted out the remnants of the congressional GOP, the real historic authoritative soul of the country has spoken. Who can doubt that (in the hypothetical case of US splitting up) that the bulk of the original 13 states would have the best claim to be the successor state to United States? To use the example of United Kingdom again in this scenario, a politician from Utah, Texas, or Alaska claiming his or her region as the most genuine successor would be like Thomas Jefferson claiming US to be the true successor to UK. We can go all day with analogies but the undeniable point is that Northeastern states is what kept and still keeps the whole 200 year long political project functioning and possible.
So the much newer peripheral settlements and tree branches of USA want political control over the trunk/roots back instead of being ruled by them? The potentially fatal and seemingly insurmountable and permanent gridlock going on in Congress all the time allows us an opportunity to examine such thoughts. Neither the regional theocratic/oligarchic faction (that is the GOP) nor the regional England leaning oligarchic faction (that is New England democrats) appears to be able to defeat each other.
Such counterproductive gridlock (in the face of the worst economic depression since the 1930s) is exactly what happens when the fine points about union size in the federalist papers become obsolete due to the growth in scale of the federal union itself. The country loses ability to eventually reach a meaningful compromise acceptable to both sides (by acceptable I don't mean people resorting to calling politicians Nazis over the hyperdiluted nature of compromises we get currently).
A congress of a smaller federal union (say 10-15 states in regional economic and cultural proximity) would create compromises that do not bring the same level of psychological hate and disappointment in the factions that didn't get the details they wanted. Since people would subjectively get more of what they want in a smaller union, their psychological sense of personal power and control is increased. They are thus "freer" by most ways that freedom is measured and defined.
Texas can potentially get wealthier if it was its own country. But how would Northeast (a region less dependent than Texas on feeding and supplying the rest of the country through commodity and food exports as well as crude ethnic exploitation) fare on its own two legs?
Not surprisingly, rather well with strong potential to be better off than it is now. The oldest, most respected, and best funded Ivy League schools are in the region and so is the concentration of intellectual, financial, and political power elites along with their family clans. That is key to successful nation building since elites decide national direction instead of the average citizenry (especially if the new country preserves the current political system without moving more towards proportional representation). A lot of old money and bloodlines create an entrenched and relatively integrated ruling class that would be able to work well together on national projects. The sheer wealth of Northeastern oligarchs is shown by the fact that as of today, most of Northeast states have higher GDP per capita than the national average. Their hands would not be politically tied on the federal level by fellow oligarchs thousands of miles away in places like Texas, California, Florida. The region would be easier to remold into a shape that resembles the fashionable role model society at the time (for Northeastern rich, that appears to be England as it has been for a long time).
NUSA is also smaller in size than potential nearby competitors which allows quicker personal communication between all demographics and further economic integration. Northeast is beginning to resemble Germany in terms of population density and will be the first major region on the continent to put quality control on how the land is organized and developed. Proximity to Europe itself would allow NUSA to enjoy greater investment and cooperation with EU. The president of NUSA would not need to stand on pick up trucks or kiss bibles to get elected. The new smaller legislative branch would be made up of people who work better together due to greater closeness of culture. The federal government overall would be closer to the serfs since it would oversee 50 million people instead of 300 million. It would be in charge of a population the size of Spain not one of 3 Germanies.
As for states outside NUSA, one can only speculate. We can just imagine the absurdity and even potential Iran/Yugoslavia type horror show that the deep south would be if it was to form a federal union (not including Texas that is) of its own. Such a situation would show the real meaning of "wanting my country back".