When nuclear-armed North Korea fired a ballistic missile over Japan this week, it sparked international condemnation. But it also raised the question: Why Japan?
Location, location, location
It might seem obvious, but geography is frequently a huge factor in geopolitical wrangling.
The Japanese archipelago forms a long string off the coast of mainland north Asia, so by definition, any regional player that wants to fire a medium- or long-range missile into the Pacific has to go over it.