In two ways:

Govern-cements break up and sorta become impotent, at least to people movement. However, local communities will have defenses against intruders. Borders will not take up every inch of space. Their will be space between each. This happens because govern-cements lose a lot of power, and people change how they comprehend property rights.

Teleportation is discovered. Making borders (lines drawn on a map) almost useless.