In the long term, maybe it's a fantastic idea. But in the short term, the economic damage of all those ports suddenly ceasing to be ports alone, to say nothing of all the other disruption, probably means the idea fundamentally has too high an activation energy to happen in any forseeable future.

(activation energy in chemistry: https://en.wikipedia.org/wiki/Activation_energy )

But very interesting to think about.

Also XKCD did a comic series that probably technically constitutes the majority of XKCD's output by area which is worth looking at: https://en.wikipedia.org/wiki/Time_(xkcd)