I remember crossing from France into Spain and back again somewhere in the early 80's, when Europe definitely still had physical borders and not realizing I had done so until it had happened. My surprise stemmed in part from the fact that on the map there was a clear line and in real life there was absolutely nothing at all. It really helped me to understand once and for all that maps are just pieces of paper and that it's the real world that counts. Of course a days walk further where the highway entered Spain you'd have been stopped and asked for your passport. But high up in the countryside nobody really cared about where precisely that border was, the path is then on this side of the border and a little while later on the other. And this was at a time when the Basque separatist movement was very active with regular bombings. So the lack of a border and associated controls was in a way something that you wouldn't expect at all.
Now, with Schengen in full effect all over Europe crossing a border is something that usually involves seeing some buildings without a purpose in the middle of a highway. The only time I have been stopped inside the Schengen area for document checks was during the COVID era and it felt pretty weird not to be able to just go from Amsterdam to Riga without such checks.
I'm not sure what the profound insight is supposed to be here. Everyone knows that borders are established by convention and agreement. That doesn't mean they don't matter.
Borders exist for the sake of the common good, in a way that's analogous to private property, which also exists for the sake of the common good. I realize this must be a strange notion for those of us raised in a culture that's been shot through with liberalism and liberal/radically individualist ideas (I have here in mind the philosophical stance, not liberal institutions), where private property is understood as prior to the common good and where the common good is conceived as something that's grudgingly ceded from private property. But traditionally, the common good was taken to be prior to private property, and private property to be something the exists for the sake of the common good because it enables human flourishing. (Incidentally, this understanding resolves ethical problems concerning the use of what would otherwise be taken to be private property during times of crisis, such as whether the taking of food from a privately owned stockpile, by starving people, during a famine would constitute theft.)
Now, how particular borders are enforced or respected or treated is a matter of prudential political judgement. Schengen is not borderless. It is itself defined by a border that is enforced by Frontex! It is precisely the Schengen border that enables free movement within Schengen. Member states have determined that free movement between them and them only is for the common good of these member states. Furthermore, just because free movement is now possible doesn't mean borders have ceased to exist. Administrative borders still exist because they circumscribe legal jurisdictions, and these may or may not coincide with ethnic boundaries or cultural regions. States have simply become more permissive about enforcing movement because of their membership in Schengen. But if a crisis were to occur, such as a flood of migrants that threatens the good of a nation's population, you can be sure that member states would control the flow of people over their borders again, if only temporarily, to contain the crisis and protect the common good of the population. Protecting the common good is, after all, the job of the state.
I would very much appreciate an explanation about why the above comment was so downvoted. You might disagree with them but it's a laid out argument definitely deserving more than an arrow down. So please tell, what is wrong with it? You disagree with the stated aim of a state? With the private vs common property? With long comments?
Now, with Schengen in full effect all over Europe crossing a border is something that usually involves seeing some buildings without a purpose in the middle of a highway. The only time I have been stopped inside the Schengen area for document checks was during the COVID era and it felt pretty weird not to be able to just go from Amsterdam to Riga without such checks.