What is a Single strong disadvantage of Japan's isolation?

Strong meaning:





ex. Why is icecream bad?





1.Because it drips on your fingers and you have to deal with licking it off after.


2.Because many icecream out there are very unhealthy for the body.





So the obviously stronger one would be '2'.





So if someone can help me by giving me a singly strong disadvantage of Japan's isolation please lol.What is a Single strong disadvantage of Japan's isolation?
Since Japan is geographically isolated, it is VIRTUALLY CUT-OFF FROM THE REST OF THE WORLD, THUS MAKING WAR, EARTHQUAKES, PLAGUES, EPIDEMICS, AND TSUNAMIS A LOT MORE DANGEROUS - since they have no where to go - being huddled up in the small coastlines of Japan.What is a Single strong disadvantage of Japan's isolation?
The have to import by sea or air many of the raw materials they need for industry, such as fuel, metals, timber, etc. This makes products more expensive to produce and leaves them vulnerable to disruptions in shipping from war or piracy.
It's likely to have bad consequences if hit by a natural disaster (earthquake or tsunami) because there are a lot of people living in such a small and isolated place.