After so many disasters and chaos in the past few months or so, do you think Japan would eventually just sink?

Question:

it's an island nation, a tiny one at that, it's really not that inconceivable to imagine the whole island sinking....

Answer:

Depends what you mean by sinking and what you mean by eventually. Eventually (in millions of years) all the current landmasses will have been changed and moved beyond recognition. Mountain ranges will have been weathered and eroded flat, flat land will turn into mountains due to tectonic plate collisions, volcanos will create new islands... Sea levels will rise and fall, exposing or submerging land, some land will be subducted into the mantle (inside the earth). Islands will become parts of massive continents and today's massive continents will be ripped apart.

In the short term it's not going to just sink, that's not what happens, as it's not floating on top of the sea.