The Internet Already is "Balkanized"

International communications have always been borderless in a controlled way. Both governments and service providers have guidelines about how and when communications can cross borders. 

Oddly enough, there are more barriers in the internet era, in large part because governments always have controlled the movement of content across borders.

So  regulation might be a bit different in the internet era, but it has not gone away, by any means. In fact, more barriers exist, compared to the days when only voice crossed borders. 

Governments routinely block some content, a process that has been obvious for some time.

source: Freedom House 

The internet is not borderless.