I dont think that our Nation will fall apart of any single issue, leastwise abortion. Though I do know people on both sides that seem entirely willing to see the Nation destroyed in order for their point of view to 'win'.
I certainly wouldn't want to see a system where people are forced to relocate in order to receive justice. What would be far worse, IMhO, is a system where large numbers of the populace simply can't get it anywhere. There are many examples, take the "War on Drugs", or the split between those who want to keep their Privacy, the ability to defend themselves, and to exercise one of the most basic and pure Rights which is to be let alone, as opposed to those who want an all-seeing, all-knowing, all-powerful federal government to keep them safe. When either mentality gains control of it at the federal level, the others won't find justice anywhere.
Thats pretty much what we have going on now, and that is only getting worse. Its why we have the highest per capita incarceration rate of any industrialized country, by far.
If I have come to realize anything, its that there are no 'perfect' solutions to the major problems. Whats good for some is always going to be bad for others, Whats wise and proper for New York City, would be a disaster in Bell Buckle Tennessee. One Man's Utopia is another man's Hell on Earth.
I run across the 'perfect' plans all the time, I hear them being hawked in the campaigns, I see the hundreds of millions of innocent corpses they have left scattered across the pages of history. Most all have had one thing in common, to one degree or another. They look better on paper than they do with a gun to your head.
In a Nation that touts itself as not only Free but Diverse, there must be room for people to live differently from one another, but peacefully and without diminishing or destroying the rights of others. Trying to make a better life is essential to human nature and human survival, its how we managed to get this far. Our People simply must be free to explore new ideas and new ways of doing things, without the risk of dragging everyone else down with them if they are wrong.
Have the 'states' made mistakes in the past? Oh yes, they certainly have. The federal government has them all beat on that score, and a mistake by the fed makes everyone suffer, and is much harder to fix. Any scheme in which success is based on everyone being made to join in, to play their assigned part whether they like it or not, whether its good for them or not, is doomed from the beginning. That is the only kind of scheme the federal government is capable of producing, and that is why it was never intended to have such power.
Our Constitutional system as written, is not perfect. It is however the closest thing to perfect Man has yet devised. Carte Blanche federalism is a giant step backward from that, not forward.