We can build up though. I might be worth 4 feet of shoreline, but my 40 foot sea view apartment is in a 50 floor apartment building, which leaves a lot of the shoreline unpopulated.

That assumes everyone wants shore view. With young kids I prefer my house to be far away from places weak/non swimmers can drawn. I know many other reasons why someone would choose to not live somewhere far from the sea if they get a choice.

Sorry, I wasn't trying to say "so it doesn't work". Obviously multi-story houses and houses not right on the shore have sea views.

> With young kids I prefer my house to be far away from places weak/non swimmers can drown.

That rules out whole countries. And misses all the fun of having water nearby. The chances of that happening are so vanishingly small that it probably is a bad guide as to where you want your kids to grow up.

~1000 American kids die a year from drowning - the rate has went down since pool fences became common. I'm not sure it's quite "vanishingly rare", though of course it's not common.

Your mention of pool fences implies that moving away from the sea doesn't necessarily help keep your kids safe from drowning.

> my 40 foot sea view apartment is in a 50 floor apartment building

So the buildings would double as a tsunami wall? Interesting, though kind of self-defeating.

Sorry, not an actual map. Just a back-of-the-envelope calculation. I'll try to find it.

if we cover all the shoreline with 10 story apartment buildings, it could be 40 ft per household! the larger problem would be having an acceptable amount of green space on the other side I think.

You can stack households on top of each other.