In general? No. Unless they have some sort of humanitarian issue such as abuse, discrimination or genocide then I am not in favor of nations breaking down into smaller and smaller parts.
This is in large part because I live in the United States and see the massive advantages to our union. I can travel for business or leisure across a continent without customs and passports, without differing currencies and laws. If anything I'd like us to reach more agreements with Canada to make for softer borders and easier exchange of currency and business.
I think when I look at the states what would happen if Texas broke off from the union? Well, it would hurt Texas and the union economically as no way the union would want it to be a success story that encourages others to follow. Within Texas how would they fight against, say, Austin wanting to break off from it and then you could witness a Balkzanization effect.
