It's not that surprising once you know that their goal is to be completely independent for their US for their military equipment.
It includes the nuclear bomb, missiles, fighter jet, aircraft carrier, submarines, even space capabilities (even if this last part has been lacking a bit lately).
They don't have the US military budget but they want the same level of technology without any ties to the US.
It means that they are exporting a lot to compensate for the high investments they are pouring into military technology.
Soy sauce and fermented food in general are full of umami flavor.